President Donald Trump was reported uninjured and other top leaders of the United States were evacuated from an annual dinner of White House correspondents after an unspecified threat. There did not immediately appear to be any injuries Saturday night, and one law-enforcement official said a shooter opened fire. The Secret Service and other authorities swarmed the banquet hall at the Washington Hilton as guests ducked under tables by the hundreds. “Out of the way, sir!” someone yelled. Others yelled to duck.

Donald Trump's expected attendance at Saturday's annual White House Correspondents' Association dinner in Washington for his first time as pre…