Munich Massacre
Also called: Munich Olympics massacre, Black September attack
Members of the Palestinian militant group Black September took the Israeli team hostage in the Munich Olympic Village. A botched rescue attempt by West German police ended with all eleven hostages dead.

Avi1111 dr. avishai teicher · CC BY-SA 4.0 · Source
Before dawn on 5 September 1972, eight armed members of Black September entered the Israeli team’s quarters at 31 Connollystraße in the Olympic Village, killed two men who resisted and took nine hostage. They demanded the release of some 200 Palestinians held in Israel and of West German far-left leaders.
That night the West German authorities had the hostage-takers flown by helicopter to Fürstenfeldbruck air base and attempted a rescue, but the operation was poorly prepared, and in the gunfight all nine hostages were killed, along with a West German policeman and five of the attackers. A memorial service was held in the main stadium the next day, and IOC president Avery Brundage declared that “the Games must go on”. Israel later hunted down those it held responsible, and West Germany created the GSG 9 counter-terrorism unit.