CAMBRIDGE, Mass. — A man has been killed in an overnight shooting in Cambridge.Middlesex County District Attorney Marian Ryan says police responded to a report of a shooting at about 12:20 a.m. Saturday on Harvard Street, near the Massachusetts Institute of Technology.Responding officers found 49-year-old Anthony Clay, of Cambridge, suffering from a gunshot wound.Clay was taken to Massachusetts General Hospital, where he was pronounced dead.The investigation is ongoing.