The authorities said the man, who did not make it into the large ballroom where Mr. Trump, top administration officials and hundreds of journalists had gathered for dinner, was carrying a shotgun, handgun and knives. The head of Washington’s police force said that investigators believed he fired at least once, and that officials were reviewing ballistics evidence and shell casings.

The NYTimes article in the OP says that they found 2 guns and a knife on the suspect.

Also the photos that Trump posted show that the suspect was stripped completely naked with his lower half being covered by a aluminum thermal blanket. This would indicate that the suspect was strip-searched.