The 5th of September 1972 brought a sad day to the Munich Olympics as 11 Israeli athletes were killed by Palestinian gunmen in what was to become known as the Munich massacre . The Olympic Flag was flown at halfmast, along with the flags of most of the other competing nations . Ten Arab nations objected to their flags being lowered to honor murdered Israelis; their flags were restored to the full mast , 6th September 1968