Israeli athletes and officials, the mayor of Paris and International Olympic Committee officials paid tribute on Tuesday to Israeli Olympic team members killed by Palestinian gunmen at the 1972 Munich Olympics.
Eleven Israelis were killed in an attack on Munich's poorly secured Olympic village where they were staying.
"The 5th of September, 1972 is the darkest day in Olympic history," IOC President Thomas Bach told the ceremony held at Israel's embassy during the second week of the Paris Olympics. "Everything was shattered with the horrific terrorist attack on the Israeli Olympic team 52 years ago."
Amid heightened geopolitical tensions over Israel's war in Gaza, the memorial ceremony, originally due to take place just before the start of the Games outside Paris City Hall, was moved to the heavily protected Israeli embassy.
"The pain remains eternal," Israeli President Isaac Herzog said via video link. "I'll never forget the tears, the shock ... the Olympics which represented joy turned into tragedy."
The Munich attack on the Israeli team by gunmen associated with the Palestinian guerrilla group Black September shocked the world, playing out in large part on live television watched by millions of people.
Eight militants infiltrated the Olympic Village and broke into the Israeli athlete apartments, kicking off a bloody 24-hour standoff that began with a struggle between the gunmen and unarmed athletes who tried to defend themselves.
The gunmen killed two athletes and took nine hostage, who were later killed after a failed rescue attempt by German police. A German policeman and five of the Palestinian gunmen were also killed in exchanges of fire after the stand-off at the Olympic village and at nearby Fuerstenfeldbruck airfield.
Three militants were captured but freed in October in exchange for hostages aboard a hijacked German airliner.
German and Olympic authorities faced bitter criticism at the time for their response to the attack.
The 1972 Games continued after the attacks and the IOC took almost half a century to comply with families' requests for an official act of remembrance at an Olympic event.
It finally held a moment of silence and mentioned the Munich victims at the Tokyo summer Olympics' opening ceremony in 2021.
For the Paris Games, Israeli competitors are being escorted by elite tactical units to and from events and given 24-hour protection throughout the Olympics, officials say.
Ahead of the Games, the Palestinian Olympic Committee joined calls for Israel to be excluded because of the war in Gaza.