Look at the editorial I was just sent from the NY Post on 9/14/01 - 3 days after collapse of WTC. Any apologies? pic.twitter.com/b6DKEOk8Px— Donald J. Trump (@realDonaldTrump) December 1, 2015
"If thousands of people were demonstrating and he saw it on television, then there must be some tape of it somewhere. If it shows up it will corroborate him. If it doesn't show up it's going to make him look really bad," Giuliani said.
Trump also posted video of radio host Curtis Sliwa saying that people were cheering when the World Trade Center towers went down.
Several other politicians from the area and independent fact-checkers have disputed Trump's claim about thousands of Muslim Americans cheering, as well as some GOP rivals.