President Donald Trump arrives to speak during the Tunnel to Towers Foundation event on the Ellipse near the White House in Washington on Tuesday.

President Trump is telling iffy 9/11 stories again.

On Tuesday, he took part in the Tunnel to Towers Foundation’s Steel Across America tour, delivering remarks from the Ellipse in Washington, D.C., in honor of the upcoming 25th anniversary of the September 11 attacks. But naturally, his appearance couldn’t pass without a bit of weirdness.

Trump did honor first responders and the nearly 3,000 victims of the attacks, posthumously awarding the Medal of Freedom to Welles Crowther, an equities trader and volunteer firefighter who died while helping people flee the collapsing South Tower. But the president also used his speech to repeat a questionable anecdote about his whereabouts and actions in the aftermath of the tragedy and later defended his recollection as questions arose.

The president told the assembled crowd that he had been working on a “big building” when the attacks took place and that he took the entire construction crew down to ground zero “right after this happened.” It was then, Trump claims, that a pair of firefighters rushed him to safety out of concern that the nearby U.S. Steel Building, which is now known as One Liberty Plaza, was at risk of collapse. Trump said Tuesday that the building was “creaking” at the time. It wasn’t clear if by “right after” he meant the day of the attacks or sometime in the following days.