A Secret Service agent who tried to shield former President John F. Kennedy from an assassin’s gunfire in 1963 died on Monday. Clint Hill, 93, died at his California home from unknown causes. He had been serving on presidential security detail for just three years when he made the move that defined his career.

Clint Hill, the Secret Service agent who ran into the line of fire to shield President John F. Kennedy and the first lady in Dallas on November 22, 1963, died Friday. He was 93 years old.