Snowden, facing arrest if he steps foot on U.S. soil, spoke via a video link to a packed house at the annual South by Southwest (SXSW) gathering of tech industry experts, filmmakers and musicians. He said the U.S. government still has no idea what material he has provided to journalists.

"I saw that the Constitution was violated on a massive scale," Snowden said to applause, adding that his revelations of government spying on private communications have resulted in protections that have benefited the public and global society.

Last year, Snowden, who had been working at a National Security Agency (NSA) facility as an employee of Booz Allen Hamilton, leaked a raft of secret documents that revealed a vast U.S. government system for monitoring phone and Internet data.

The leaks deeply embarrassed the Obama administration, which in January banned U.S. eavesdropping on the leaders of friendly countries and allies and began reining in the sweeping collection of Americans' phone data in a series of limited reforms triggered by Snowden's revelations.

Major companies also tightened up safeguards, but Snowden said that is still not enough to protect privacy properly, calling for stepped-up encryption that would make mass government surveillance too costly to conduct.

"The government has gone and changed their talking points. They have changed their verbiage away from public interest to national interest," he said, adding that this poses the risk of losing control of representative democracy.

He said the government's priority has been an expansive and ill-executed system of massive information collection instead of protecting the vast amounts of intellectual property that supports the U.S. economy.

"We've got the most to lose from being hacked," Snowden said.

U.S. Representative Mike Pompeo, a Republican from Kansas, wrote to SXSW organizers, calling on them to withdraw the invitation to Snowden, a man he said deceived his employer and his country.

"Rewarding Mr. Snowden's behavior in this way encourages the very lawlessness he exhibited," Pompeo wrote.

To many in government and at the NSA, Snowden is a traitor who compromised the security of the United States. But for many at the conference he is a hero who protected privacy and civil liberties.

"To me, Snowden is a patriot who believed that what he did was in the best interests of his country," said Roeland Stekelenburg, creative director at the Dutch Internet firm Infostrada.

NSA officials were not immediately available for comment.

Imagine reading the next web article twice as quickly as this one - and understanding more of it too.

That's the claim made by Boston-based Spritz, which aims to revolutionise speed reading one word at a time.

Drawing on science established in the 1960s, the premise is that by flashing up single words in quick succession and allowing your gaze to remain largely in the same place on a screen, the brain can digest information far more effectively than your eye scanning across a page. Counter-intuitively, the faster you read using the method, the more you understand, because you are apparently more focused.

Admittedly, "Spritz-ing" does take a little practice, and it is better suited to emails and web pages than novels, where a more leisurely approach might be called for.

Try it for yourself by clicking on the Spritz demo button.

Having spent three years in "stealth mode" developing the tech, the start-up made headlines last month when Samsung said it would incorporate the tech into its Gear smartwatch, its small screen ideally suited to the concept. In the week following the announcement, Spritz's founder Frank Waldman tells me that he had to speed-read his way through more than 7,000 submissions from software developers wanting to incorporate his breakthrough. The power of MIT

Mr Waldman, like so many in the region, hails from the Massachusetts Institute of Technology (MIT), just across the river from Boston, in Cambridge. For 150 years MIT has been turbo-charging Boston's tech engine.

Its influence is hard to overstate: MIT alumni have produced companies that generate annual world revenues of $2 trillion (£1.2 trillion), with hundreds of patents ranging from biotechnology to computing.

And looking to the future, the region looks to be strategically well-placed.

"Because innovation is moving towards a hybrid model of the digital and the material, Massachusetts is once again a place for that, because this is a place where we actually make things," argues Fiona Murray, dean of innovation at MIT.

One particularly fascinating project is called inFORM

Take a 3D camera to capture your hand gestures, relay the information over the internet and convert it back into physical movement; a matrix of 900 pins driven by small motors rises or lowers to simulate your original movement.

Dozens of ships and aircraft from 10 countries scoured the seas around Malaysia and south of Vietnam as questions mounted over possible security lapses and whether a bomb or hijacking attempt could have brought down the Boeing 777-200ER which took off from the Malaysian capital, Kuala Lumpur.

The area of the search would be widened from Tuesday, Azharuddin Abdul Rahman, the head of Malaysia's Civil Aviation Authority, told reporters.

A senior police official told Reuters that people armed with explosives and carrying false identity papers had tried to fly out of Kuala Lumpur in the past, and that current investigations were focused on two passengers who were on the missing plane with stolen passports.

"We have stopped men with false or stolen passports and carrying explosives, who have tried to get past KLIA (airport) security and get on to a plane," he said. "There have been two or three incidents, but I will not divulge the details."

Interpol confirmed on Sunday at least two passengers used stolen passports and said it was checking whether others aboard had used false identity documents.

Azharuddin said a hijacking attempt could not be ruled out as investigators explore all theories for the loss of Malaysia Airlines Flight MH370.

"Unfortunately we have not found anything that appears to be objects from the aircraft, let alone the aircraft," he told a news conference. "As far as we are concerned, we have to find the aircraft. We have to find a piece of the aircraft if possible."

Azharuddin also said the two men with stolen passports did not look like Asians, but he did not elaborate. Airport CCTV footage showed they completed all security procedures, he said.

"We are looking at the possibility of a stolen passport syndicate," he said.

About two-thirds of the 227 passengers and 12 crew now presumed to have died aboard the plane were Chinese. The airline said other nationalities included 38 Malaysians, seven Indonesians, six Australians, five Indians, four French and three Americans.

Ukrainian activists trying to cross into Crimea to show solidarity with opponents of last week's Russian military takeover there said they were halted by men in uniforms of the now outlawed riot police. One of these fired at close range, hitting a man in the chest, apparently with rubber bullets.

With diplomacy at a standstill, Russia said the United States had spurned an invitation to hold new talks on resolving the crisis, the worst East-West standoff since the Cold War - though Washington later said a meeting of foreign ministers was possible this week, if Moscow shows it is ready to "engage".

The U.S.-led NATO defense alliance said AWACS early warning aircraft, once designed to counter feared Soviet nuclear missile strikes, will start reconnaissance flights on Tuesday over Poland and Romania to monitor the situation in Ukraine, flying from bases in Germany and Britain.

British Prime Minister David Cameron told Germany's Bild newspaper, however, that Western powers were not considering military action and wanted a diplomatic solution. European Union governments are considering sanctions against Russia.

Ukrainian Prime Minister Arseny Yatseniuk, who said he would address the U.N. Security Council on Thursday, blamed the crisis on Russia and accused Moscow of undermining the global security system by taking control of Crimea.

Ukraine's new justice authorities issued warrants for the arrest of Crimea's pro-Russia leaders on Monday, six days before a referendum they have called to join the region to Russia.

Russian forces have in little more than a week taken over military installations across Crimea, home to the Russian Black Sea Fleet and Russian territory until Soviet leader Nikita Khrushchev gave it to Ukraine in 1954.

Pro-Russian separatists have taken control of the regional parliament, declared Crimea part of the Russian Federation and announced the referendum for Sunday to confirm this. President Vladimir Putin says Moscow is acting to protect the rights of ethnic Russians, who make up a majority of Crimea's population, after Ukraine's president Viktor Yanukovich was ousted last month in what Russia calls a coup.

BASE TAKEOVER

It would allow developers to create wearable devices such as smartwatches and fitness trackers using the Android operating system.

Google's senior vice-president of Android, Chrome and apps said: "We want to develop a set of common protocols by which they can work together."

The kit would be available in two weeks' time, Sundar Pichai added. Samsung's Galaxy Gear smartwatch did run a version of Android - but after concerns over its interface and battery life, it switched to the Tizen software platform for its latest watch, the Gear 2.

Google Glass is the company's main foray into wearables so far. The device includes eyeglass frames equipped with a camera and small display controlled by voice command. The product is not yet on general sale but is being tested by selected people.

"Google is taking wearables seriously and it wants everyone else to," said John Delaney, vice-president of mobility research at analyst firm IDC.

"The industry thinks wearables is the next big thing as sales of smartphones start to plateau in developed markets and this is the latest attempt to build momentum behind it," he said.

"Google would be a competitor in the market but also an enabler if it helps Android developers."

Apple is reportedly working on a smartwatch that could use the operating system used on its iPhones and iPads.

Android is already the most used operating system on smartphones and more than 1.1 billion devices running Android are expected to ship this year, according to the research firm Gartner.

Geoff Blaber, an analyst at CCS Insight, said it was a logical move for Google.

"From Google's perspective, it's essential it introduces some consistency into a fast-fragmenting wearables space," he said

"Without a consistent software development kit there was a danger that the wearables space would quickly result in a fragmented array of implementations that would make it harder for Google to control and monetise.

Judge Harlin Hale in Dallas granted temporary bankruptcy protection to Mt. Gox, which had filed for bankruptcy protection in Japan in February. Attorneys for Mt. Gox said without bankruptcy protection the company would be irreparably harmed by a proposed class action in Chicago federal court and a breach of contract case in Seattle federal court.

Mt. Gox filed for bankruptcy in Japan last month after it said it may have lost 750,000 of its customers' bitcoins as part of an attack by hackers.

The plaintiff leading the Chicago lawsuit was scheduled on Tuesday to ask a federal judge to freeze Mt. Gox's U.S.-based servers and other computer equipment and to set up a trust over Mt. Gox's assets. Mt. Gox's founder, Mark Karpeles, was scheduled to be deposed later this month in the Seattle lawsuit.

The attorney leading the class action blasted the bankruptcy as a ruse.

"This case involves a massive fraud," said Steven Woodrow, an attorney leading the class action, told Hale. "They claim incredibly that they will preserve assets and protect assets by entrusting the servers and other property to Mr. Karpeles. Respectfully, your honor, that is the definition of the fox guarding the henhouse."

Mt. Gox said in papers filed with the Dallas court that the hacking attack was the subject of an intense investigation that indicated so far the bitcoins were lost as a result of a flaw in the software algorithm that underlies bitcoin, the digital currency.

An attorney for Coinlab Inc, which sued Mt. Gox in Seattle for breaching a contract last year, said her client was troubled by what appeared to be fraudulent behavior by Karpeles in the days leading up the U.S. bankruptcy filing.

"We don't have proof yet but we do have concerns about the movement of hundreds of millions of dollars in bitcoins over the weekend, moved by Mr. Karpeles," said Jane Pearson, an attorney with Foster Pepper. Mt. Gox's attorney, David Parham, denied there was any fraud and said he believed Karpeles and Mt. Gox were complying with the Japanese bankruptcy proceeding.

The Chapter 15 filing allows Mt. Gox to ask the U.S. Bankruptcy Court to recognize its foreign bankruptcy and to assist in the Japanese proceedings by protecting its U.S.-based assets.

Icahn, who owns just over 2 percent of the e-commerce company, has been pressuring eBay for weeks to spin off its PayPal payments business. He has also repeatedly accused eBay of poor corporate governance.

The billionaire nominated Icahn Enterprises LP employees Daniel Ninivaggi and Jonathan Christodoro, both of whom Icahn regularly nominates to boards.

The chairman of eBay's corporate governance and nominating committee, Richard Schlosberg III, said the board considered both but rejected them because "neither nominee has relevant experience or expertise."

EBay said since each Icahn nominee currently sits on four public company boards, they are not in compliance with eBay's guidelines on "overboarding."

EBay founder and Chairman Pierre Omidyar in a statement urged shareholders to support the company's slate, which includes Chief Executive John Donahoe.

The company also said Donahoe's 2013 compensation fell by more than half to $13.8 million. That largely reflects the board's decision in 2012 to give him a one-time award of $14.8 million in performance share units, although eBay's weaker-than-expected financial performance also hurt his pay.

The company did not in its preliminary proxy statement set the date for its next annual shareholders meeting, which is expected to take place in the spring.

Icahn has sparred with eBay management via open letters and press releases since January, when the pugnacious billionaire made an unsolicited proposal for eBay to hive off PayPal.

The company has repeatedly said PayPal and eBay are better off as part of the same company.

In a fresh missive on Monday, Icahn accused Donahoe of "inexcusable incompetence" and said the fast-growing PayPal could "wither" if it remains part of eBay.

"PayPal may well go the way of other former technology greats such as Blackberry, Dell, Eastman Kodak, Polaroid, Nintendo, Xerox, Sony, Palm, and AOL," Icahn said.

EBay called Icahn's comments "false and misleading."

But Josep Maria Bartomeu told the BBC that the Spanish champions had done nothing wrong.

Spain's authorities accuse Barcelona of tax fraud over the transfer.

"It's embarrassing because we think we are right," Bartomeu said. "We think we did things properly, that everything was done in the correct and best way."

The club were formally accused of tax fraud in February, when a judge in Spain ruled there was enough evidence to continue investigations into the transfer.

It is alleged that Barcelona tried to evade £7.58m in taxes after signing the Brazilian forward from Santos in June last year. Bartomeu added: "Barcelona acted in the proper way but if somebody thinks that there is damage to the name of Barcelona then there is damage to be repaired."

Insisting the club had done nothing wrong, he added: "We are not happy with the situation but we will defend our club very strongly."

In January, Sandro Rosell resigned as Barcelona president following accusations he misappropriated money. He is also being investigated but denies any wrongdoing.

At the time of the move, Barcelona said the transfer was worth £48.6m but, after questions were raised by a member of the club, they were forced to release documents showing the full cost to be more than £71m.

A fortnight ago, after a judge decided the investigation into the transfer could continue, Barcelona made a "voluntary contribution" of more than £11m in taxes. So far, there is no sign the payment will bring an end to the criminal investigation.

Bartomeu said: "We paid because of prudence, because there is a possible different interpretation. So we want to be prudent. We don't want to take any risks.

"Barca is a very well known brand name in the world and we have to take care of Barca of the club and doing this is prudent situation to keep the good image of our club.

Malaysia Airlines flight MH370 vanished after climbing to a cruising altitude of 35,000 feet between Kuala Lumpur and Beijing in the early hours of Saturday. Search teams have not been able to make any confirmed discovery of wreckage in seas beneath the plane's flight path almost 48 hours after it took off.

"The fact that we are unable to find any debris so far appears to indicate that the aircraft is likely to have disintegrated at around 35,000 feet," said the source, who is involved in the preliminary investigations in Malaysia.

If the plane had plunged intact from such a height, breaking up only on impact with the water, search teams would have expected to find a fairly concentrated pattern of debris, said the source, speaking on condition of anonymity because he was not authorized to speak publicly on the investigation.

The source was speaking shortly before Vietnamese authorities said a military plane had spotted an object at sea suspected to be part of the missing airliner.

Asked about the possibility of an explosion, such as a bomb, the source said there was no evidence yet of foul play and that the aircraft could have broken up due to mechanical issues.

Malaysian authorities have said they are focused on finding the plane and have declined to comment when asked about the investigations.

However, the source said the closest parallels were the explosion on board an Air India jetliner in 1985 when it was over the Atlantic Ocean and the Lockerbie air disaster in 1988. Both planes were cruising at around 31,000 feet when bombs exploded on board.

Canadian and Indian police have long alleged the Air India bombing was conducted by Sikh extremists living in western Canada as revenge on India for the deadly 1984 assault on the Golden Temple in Amritsar, Sikhism's holiest shrine.

The bombing of Pan Am Flight 103 over the Scottish town of Lockerbie killed 259 passengers and crew and another 11 people on the ground. A Libyan intelligence officer was convicted for the attack.

International police agency Interpol has said at least two of the passengers on board the Malaysian plane, and possibly more, used passports listed as missing or stolen on its database.

Shortly after I don Oculus Rift, the mind-blowing virtual reality 3D headset from Oculus VR that is likely to take the gaming market by storm whenever it finally ships. For 45 seconds I watch the virtual alter ego I just created explore digital worlds. As I move my head around Oculus I visit different parts of these virtual worlds — with the scene alternating between an arctic frozen tundra, a marshy volcanic environment and a desert landscape.

I'm taking part in a pretty awesome computational photography tech demo at South by Southwest, courtesy of Microsoft Research and the guys most responsible for it, James George, a Brooklyn-based media artist and his partner Alexander Porter, an "experimental photographer." Microsoft is housing a showroom during SXSW as a way to show off something really cool, and to promote products including a new game for the Xbox One.

The reconstruction of my body in the Microsoft Research demo is made possible by four Kinect cameras that are paired with four high-end Canon EOS 5D Mark III digital cameras. My body image is captured from all sides.

The Kinect cameras provide a sense of depth; the DSLRs add the color textures on top of your virtual clone, Porter says.

"When you see yourself in the image it's not so abstract," he says. "This is sort of the digital world entering the real world and vice versa."

Every pixel is accounted for in its proper space. Porter compares the experience as a cross between Tron and the Looney Tunes character Marvin the Martian. "So many of the techniques and the tools we have now were previously science fiction objects."

Still, the company has no immediate commercial plans for for the technology. But you can easily envision how this might eventually be deployed in cinema, interactive games, possibly even education.

George is mainly interested in the artistic possibilities. "Art has a practical place in the world," he says.

"It's important that we look at these technologies not as products that are coming out but how they make us feel, the stories that we tell through them, the emotions we can have when we share (these) experiences."

That still seems a ways off.

More than 1,000 workers walked off the job last week at the factory in Shenzhen, bordering Hong Kong, after managers on March 3 announced the terms of their transfer to new ownership under Chinese PC maker Lenovo Group Ltd.

Lenovo agreed in January to pay $2.3 billion for International Business Machine's low-end server business.

The strike, which continued into Sunday, fits a growing pattern of industrial activism that has emerged as China's economy has slowed. A worsening labor shortage has shifted the balance of power in labor relations, while smartphones and social media have helped workers organize and made them more aware than ever of the changing environment, experts say.

"Chinese workers, after being exploited for so long, are now more and more aware of their rights and united. They have more of an idea of collective action," said labor lawyer Duan Yi.

A report by the advocacy group China Labour Bulletin last month said it had talled 1,171 strikes and protests from the beginning of June 2011 to the end of December 2013.

Many worker protests during that time in Guangdong province, a manufacturing hub where the IBM server factory is situated, were sparked by the closure, merger or relocation of factories.

In November, hundreds of employees stopped work at a Nokia factory in Dongguan, near Shenzhen, complaining of changes following Nokia's sale of its mobile phone business to U.S. software giant Microsoft Corp.

Lawyer Duan is seeking arbitration for a group of 70 Nokia workers who were laid off at the time.

Last August, 5,000 workers in eastern Shandong Province went on strike to protest Apollo Tyres Ltd's proposed $2.5 billion acquisition of U.S.-based Cooper Tire & Rubber Co. The deal was eventually scuttled and Cooper reported this month that the work stoppage in China had cut operating profit by $29 million in the third quarter.

The labor shortage has pushed up wages, impelled employers to cast a wide net to find employees and enhance benefits to retain staff. Workers have gained leverage.

"Workers know they have greater power," said Geoffrey Crothall, a China labor expert with China Labour Bulletin. IBM said last week the terms offered to the workers at the International System Technology Company factory in Shenzhen were "comparable in aggregate to what they currently are receiving" and severance packages would be "equitable".

Putin defended breakaway moves by pro-Russian leaders in Crimea, where Russian forces tightened their grip on the Ukrainian region by seizing another border post.

As thousands staged rival rallies in Crimea, street violence flared in Sebastopol, when pro-Russian activists and Cossacks attacked a group of Ukrainians.

Russian forces' seizure of the Black Sea peninsula has been bloodless but tensions are mounting following the decision by pro-Russian groups there to make Crimea part of Russia.

The operation to seize Crimea began within days of Ukraine's pro-Russian President Viktor Yanukovich's flight from the country last month. Yanukovich was toppled after three months of demonstrations against a decision to spurn a free trade deal with the European Union for closer ties with Russia.

Ukrainian Prime Minister Arseny Yatseniuk will hold talks with President Barack Obama in Washington on Wednesday on how to find a peaceful resolution to the crisis, the White House said.

One of Obama's top national security officials said the United States would not recognize the annexation of Crimea by Russia if residents vote to leave Ukraine in a referendum next week.

"We won't recognize it, nor will most of the world," deputy national security adviser Tony Blinken said.

INTERNATIONAL LAW

Putin declared a week ago that Russia had the right to invade Ukraine to protect Russian citizens, and his parliament has voted to change the law to make it easier to annex territory inhabited by Russian speakers.

Speaking by telephone to Merkel and British Prime Minister David Cameron, Putin said steps taken by authorities in Crimea were "based on international law and aimed at guaranteeing the legitimate interests of the peninsula's population," the Kremlin said.

A German government statement, however, said the referendum was illegal. "Holding it violates the Ukrainian constitution and international law."

Merkel also regretted the lack of progress on forming an "international contact group" to seek a political solution to the Ukraine crisis and said this should be done urgently.

On Thursday, Merkel said if a contact group was not formed in the coming days and no progress was made in negotiations with Russia, the European Union could hit Russia with sanctions such as travel restrictions and asset freezes.