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Protestors walk towards Baltimore Police Department’s Western District police station during a march and vigil over the death of Freddie Gray in Baltimore, Maryland
Police with guns drawn on Friday search for a suspect in Watertown, Massachusetts. A Massachusetts Institute of Technology campus police officer was shot and killed late on Thursday night at the school’s campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge.