I heard a noise, I thought it was a tray falling: Donald Trump after shooting at White House event

After gunshots were fired at venue of White House Correspondents' Dinner, US President Donald Trump said, "I heard a noise and sort of thought it was a tray...I thought it was a tray going down." He added, "I've heard that many times...It was pretty loud noise...But it was a gun, and some people really understood that pretty quickly...Other people didn't."