US Secretary of State Hillary Clinton has joined calls urging the International Olympic Committee to commemorate the massacre of 11 Israeli athletes by Palestinian gunmen at the 1972 Munich games with a moment of silence at the opening ceremony of this year's games in London. The Associated Press reported that a senior state department official said Clinton wrote to the Olympic committee president to hold what was termed an "appropriate memorial event" in London for the victims. A diplomatic source familiar with the letter said Clinton specifically urged the IOC to reverse its decision not to hold a moment of silence to mark the 40th anniversary of the tragedy at Friday's opening ceremony in London. The Olympic Committee president, Jacques Rogge, says the opening ceremony is not appropriate for such a commemoration, but that the IOC is honoring the 11 Israeli athletes and coaches killed in Munich at other events. A campaign for a moment of silence at the games opening ceremony has gathered more than 100,000 signatures and support from world leaders, including US President Barack Obama. Anke Spitzer and Ilana Romano, the widows of two of the Israeli athletes murdered in Munich, are asking Olympics spectators to stand and observe a minute of silence when Rogge rises to speak at Friday's opening ceremony. Spitzer told a news conference in London that the athletes were killed in an Olympic venue and should be honored there.