Thousands of supporters of Egypt's Muslim Brotherhood stood their ground in Cairo on Sunday, saying they would not leave the streets despite "massacres" by security forces who shot dozens of them dead.
Egypt's ambulance service said 72 people were killed in Saturday's violence at a Cairo vigil by backers of deposed President Mohamed Mursi, triggering global anxiety that the Arab world's most populous country risked plunging into the abyss.
Mursi's Brotherhood, which won repeated elections after the fall of autocrat Hosni Mubarak in 2011, accuses the military of reversing the uprising that brought democracy to Egypt and demands his reinstatement.
"They will not be content until they bring back everything from the era of the corrupt, murderous security and intelligence state," senior Brotherhood official Essam el-Erian said on Facebook. "They've stepped up their efforts to do so by committing massacres never before seen in Egyptian history."
The Interior Ministry has rejected eyewitness accounts that police opened fire on the crowds and a public prosecutor has launched a probe into the violence, investigating 72 suspects for an array of crimes including murder and blocking streets.
Although Cairo was quiet on Sunday, violent clashes rattled the Suez Canal city of Port Said, with a 17-year-old youth killed in fighting between the pro- and anti-Mursi camps and a further 29 people injured, security sources said.
The violence has deeply polarized Egypt, with its secular and liberal elite so far showing little sympathy for the Brotherhood or reservations about the return to power of a military which ruled for 60 years before the 2011 uprising.
However, in one of the first signs of doubt from within the interim cabinet installed after the military takeover, Deputy Prime Minister for Economic Affairs Ziad Bahaa El-Din said the government must not copy the "oppressive" policies of its foes.
"Our position must remain fixed on the need to provide legal guarantees not only for the members of the Brotherhood, but for every Egyptian citizen. Excessive force is not permitted," El-Din wrote on Facebook.
And in another sign of unease, the Tamarud youth protest movement, which mobilized millions of people against Mursi and has fully backed the army, expressed alarm at an announcement by the interior minister that he was reviving the feared secret political police shut down after Mubarak was toppled.
"DEVOTED SON"
Saturday's killings took place the day after mass rallies called by military chief Abdel Fattah al-Sisi, who said he wanted public backing for a crackdown on "terrorism".