WASHINGTON—An officer died after being stabbed Tuesday during a burst of violence at a transit station outside the Pentagon, and a suspect in the incident was shot by law enforcement and died at the scene, officials said. The Pentagon, the headquarters of the U.S. military, was temporarily placed on lockdown after gunshots were fired Tuesday morning near the entrance of the building, A Pentagon police officer who was stabbed later died, according to officials who were not authorized to discuss the matter and spoke to The Associated Press on condition of anonymity. More details about the violence were expected at a Pentagon news conference. The connection between the shooting and the stabbing of the officer was not immediately clear. The authorities did not immediately provide details or the sequence of events. The incident occurred on a Metro bus platform that is part of the Pentagon Transit Center, according to the …