West Palm Beach, Fla. (CNN)President Donald Trump made a stunning claim Saturday, alleging without offering evidence that his predecessor, Barack Obama, wiretapped his phones at Trump Tower ahead of the 2016 election.

"Terrible! Just found out that Obama had my 'wires tapped' in Trump Tower just before the victory. Nothing found. This is McCarthyism!" Trump tweeted early Saturday morning in one part of a six-tweet tirade that began just after 6:30 a.m.