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A gunman shot and killed a Florida police officer and injured three others Thursday, prompting a massive manhunt and a lockdown of several Miami-area schools, officials said.
Sean Sherwin Labeat, 25, wearing a bullet-proof vest, fired a high-powered weapon and fled the scene after officers approached his vehicle for a traffic stop, according to police.
Miami-Dade County Mayor Carlos Alvarez, a former police officer, said the "extremely violent" suspect "assassinated" a police officer.