The prime suspect in Saturday night’s shooting of an off-duty Border Patrol agent in a Manhattan park is an “illegal alien,” according to the Department of Homeland Security — a revelation that prompted Mayor Eric Adams to demand Sunday that he and other “violent migrants” in the Big Apple be dealt with “quickly and swiftly.

“On the evening of July 19, a U.S. Customs and Border Protection @CBP officer was shot in what looks like an attempted robbery. The officer, who was off duty at the time, is currently in the hospital...