Updated

Marking the 10-year anniversary of the Rwandan genocide, President Paul Kagame (search) lashed out at the international community Wednesday for failing to stop the slaughter, and pledged that if another genocide should happen, Rwanda would be the first to send troops to stop it.

While he acknowledged that the Rwandan people were ultimately responsible for the massacres that claimed more than 500,000 lives in 100 days in 1994, he said world powers refused to do anything to stop the killing, which eventually ended when his rebel forces seized control of the country.

Kagame said Rwanda (search) would never stand by and allow widespread slaughter to take place unchecked.

"God forbid, but if a similar situation was to occur anywhere else ... we will be available to come and fight to protect those who will be targeted," Kagame told a crowd of thousands at a stadium in Kigali. Western and United Nations (search) leaders were conspicuous in their absence.

Rwanda will act because "the last 10 years have shaped us differently and have given us the spirit to be able to stand up and fight ... in defense of others who are targeted in a genocide," Kagame said.

The central African country fell quiet at noon Wednesday as it observed three minutes of silence in tribute to those hacked to death by their neighbors or shot by the army and Hutu militias following orders of the extremist Hutu government then in power.

As the ceremonies continued, people in the stands broke into tears. Others started screaming hysterically and had to be carried off into white tents set up by the Red Cross. Members of the national choir wept as they sang.

France, irked by accusations that it was partly to blame for the genocide (search), pulled its representative out of the commemoration in Kigali.

"Accusations that are grave and contrary to the truth have been made against France," the Foreign Ministry said.

Kagame said in his speech that the French "consciously trained and armed" government soldiers and militias who carried out the killings of more than half a million people and "knew they were going to perpetrate a genocide."

When the 100-day slaughter began, the U.N. had 2,519 peacekeepers in Rwanda. The most heavily armed U.N. contingent was a 450-member Belgian battalion, but Brussels withdrew days after Hutus killed 10 Belgian soldiers on April 7, 1994.

Other U.N. troops were busy "tanning at the pool" in neighboring Uganda and monitoring its border to ensure that weapons did not reach Kagame's rebels, who were fighting to end the slaughter, Ugandan President Yoweri Museveni said during the ceremony. U.N. troops at the time had been withdrawn from Rwanda and were staying at hotels in Uganda.

On April 21, as the killing raged, the U.N. Security Council passed a resolution to reduce the U.N. force in Rwanda to a token 270 troops. On May 16, the Security Council passed another resolution to send some 5,500 troops, but they didn't begin to arrive until after the genocide had ended.

"We must correct the mistakes we made in our history," Belgian Prime Minister Guy Verhofstadt told the crowd in Kinyarwanda, the national language.

South African President Thabo Mbeki criticized the United Nations for abandoning Rwanda "as Africans were exterminated like pernicious vermin."

But Kagame was the most critical of the international community.

"All these powerful nations regarded 1 million lives as valueless, as another statistic and could be dispensed with," Kagame said, referring to all of the people killed in Rwanda between 1990 and the end of the genocide in 1994.

In Washington, President Bush urged the international community to bring to justice those responsible for the genocide. Bush called the slaughter of more than 500,000 people "one of the most horrific episodes of the 20th century."

Earlier, genocide survivors gathered on a hillside to bury the remains of hundreds of victims recovered from pit-latrines and mass graves, marking the beginning of a week of mourning.

Kagame then lit a flame that will burn for 100 days at the new Kigali National Memorial Center.

In Geneva, U.N. Secretary-General Kofi Annan called on the international community to stay alert to prevent massacres like that in Rwanda.

"We cannot afford to wait until the worst has happened, or is already happening, or end up with little more than futile hand-wringing or callous indifference," Annan told the U.N. Human Rights Commission.

In New York, U.N. Undersecretary-General Catherine Bertini rang the Japanese peace bell in front of the United Nations headquarters, and about 500 U.N. staffers observed a minute of silence. Similar ceremonies were held in cities worldwide; in Rome, the lights at the Colosseum turned from white to gold Wednesday night in remembrance of the genocide victims.

Annan did not travel to Rwanda for the memorial ceremonies because he wanted to set out an anti-genocide plan involving the human rights commission, U.N. spokeswoman Marie Heuze told The Associated Press.

The international community's failure to stop the killing is a source of embarrassment for Annan, who was head of U.N. peacekeeping at the time. Both Annan and former President Clinton have apologized for failing to intervene.

The genocide began hours after the mysterious downing of the plane carrying President Juvenal Habyarimana on April 6, 1994. Tutsis who now dominate the government say the slaughter began April 7 in part because they don't want the date to coincide with the shooting down of Habyarimana's plane — an event with political meaning for radical Hutus.