ARUSHA, Tanzania — The Canadian who commanded United Nations peacekeepers during the Rwandan genocide said Thursday that world leaders were responsible for the slaughter because they feigned ignorance of what was taking place and did nothing to stop it.

Retired Lt.-Gen. Romeo Dallaire told the UN Criminal Tribunal for Rwanda that he could do little to blunt the genocide that took the lives of at least 500,000 minority Tutsis and politically moderate Hutus.

The UN force had a limited mandate and an insufficient number of troops and weapons, and that appeals for reinforcements were rejected, Dallaire told the court.

He specifically mentioned France, the United States and Belgium, the former colonial ruler which had the largest number of UN troops in Rwanda, as being "unco-operative."

"... I did not get intelligence information from them," he said.

Belgium ordered the withdrawal of its peacekeepers, the backbone of the operation, shortly after Rwandan troops killed 10 of their soldiers.

Dallaire was being cross-examined by Raphael Constant, lead lawyer for Col. Theoneste Bagosora, the alleged mastermind of the genocide who took control of Rwanda after the president's plane was shot down on April 6, 1994.

Bagosora, Brig.-Gen. Gratien Kabiligi, Col. Anatole Nsengiyumva and Maj. Aloys Ntabakuze have pleaded not guilty to charges of genocide and crimes against humanity in the slaughter that went on for 100 days. Dallaire, the 37th person to testify, is considered a key witness in the trial.

Dallaire described how the security situation deteriorated in the months before the killing began and how one of the main Hutu political parties, the CDR, was based on hatred of Tutsis. He denied Constant's assertion that he was pro-Tutsi.

"I took my decisions independently," Dallaire said.

He also explained how Bagosora hired military instructors from Togo to train Hutu militias to kill Tutsis. He was expected to continue his testimony Friday.

Earlier, the tribunal sentenced a former education minister to life in prison for his role in the genocide.

Judge William Sekule said the tribunal had found Jean de Dieu Kamuhanda, 51, guilty of genocide and extermination, but acquitted him of eight other charges of crimes against humanity.

"The chamber finds that the accused participated in the killings in Gikomero parish compound by ordering Interahamwe (militia), soldiers and policemen to kill members of the Tutsi ethnic group, instigating other assailants and by abetting in the commission of the crime through the distribution of weapons and by leading the attackers," Sekule said.

The judge recalled how witnesses described seeing Kamuhunda arrive at the parish in his car, bringing with him armed militiamen to kill Tutsis who had taken refuge at the church. The militiamen used machetes, guns and grenades in the massacre, the judge said.

Sekule rejected Kamuhanda's alibi that he was at home in Rwanda's capital, Kigali, when the massacres took place on April 12, 1994.

"I am not happy with the sentence, and I will consider appealing after consulting my client tomorrow," defence lawyer Aricha Conde said.

Kamuhunda had pleaded not guilty to all the charges. He was arrested in Bourges, France, in November 1999 and extradited to the tribunal. The court was set up in 1994 and Kamuhunda was the 17th person convicted.