In a "Reality Check" segment that compiled multiple statements Trump has made about 9/11 over the years, Avlon first took the president to task for claiming that he helped clear rubble at the site of the World Trade Center after it collapsed after being struck by airplanes.
"There's no record of Donald Trump being at the pile at ground zero," said Avlon, who at the time was working as a speechwriter for then-New York Mayor Rudy Giuliani.
Avlon then slammed Trump for slandering Muslim residents in New Jersey, whom he falsely accused of celebrating the terrorist attack in New York, and also hammered the president for lying about 9/11-related charitable donations.
"Trump said he'd donate $10,000 to the Twin Towers Fund -- there's no record of that," he said. "There's actually no record of 9/11-related donations from the alleged billionaire before he ran for president. And with so many firefighter funerals held at St. Patrick's Cathedral, just four blocks from Trump Tower, there's also no record of Trump attending a service to pay his respects."
Watch the video below.