Washington (CNN) President Donald Trump said Monday he would have stormed into the Florida high school to stop the gunman perpetrating the nation's latest mass shooting "even if I didn't have a weapon" as he lambasted the inaction of a sheriff's deputy assigned to the school.

"You don't know until you test it, but I think, I really believe I'd run in there, even if I didn't have a weapon, and I think most of the people in this room would have done that too," Trump told a gathering of US governors at the White House.

Signaling more than one sheriff's deputy was at fault, Trump said the Broward County Sheriff's deputies who remained outside the school as the shooting unfolded "weren't exactly Medal of Honor winners" and said "the way they performed was frankly disgusting."

"The way they performed was really a disgrace," Trump added.

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