KIGALI, April 4 (Reuters) - The 1994 Rwandan genocide claimed 937,000 victims according to a census the Rwandan government conducted in 2001, a cabinet minister said on Sunday.

The figure emerged as the country prepared to mark 10 years since the massacres began with a memorial on Wednesday for the ethnic Tutsis and politically moderate Hutus killed in 100 days of slaughter that the outside world did little to prevent.

Estimates of the genocide's death toll have long conflicted, ranging from 500,000 to one million people killed. The International Criminal Tribunal for Rwanda, created by the United Nations to prosecute perpetrators, estimates that "some 800,000 Rwandans were killed" between April and July 1994.

Robert Bayigamba, Rwanda's Minister for Youth, Culture and Sports, said the census was carried out by the ministry of local government. He added that the government figure could climb much higher after the completion of local trials where many defendants are expected to testify about the people they killed.

"These are the people who died during the 100days of mayhem and who we were able to find out their names, age, their places of birth and where they were killed," Bayigamba said of the new figure.

"We certainly think that it will be over one million - we shall come up with the exact figure after the Gacaca courts are over because of the confessions that will lead us to new findings during the Gacaca proceedings," said Bayigamba.

Gacaca are village gatherings or "grass roots" courts, where the traditional form of justice is being applied in an effort to expedite the trials of some 100,000 suspects charged with genocide-related crimes.

The courts have been criticised for not meeting judicial standards, and are slated to start in June.

Rwanda's genocide began on April 6, 1994, after a plane carrying the Rwandan and Burundian presidents was shot down.

The crash triggered an attempt by extremists from the ethnic Hutu majority to exterminate the minority Tutsis and Hutu moderates, hoping to preserve the Hutus' decades-long political dominance in the country of about eight million.

In July 1994, the rebel group Rwandan Patriotic Front, formed by Tutsis in exile and fighting a civil war since 1990, defeated the Hutu regime and ended the killing.

U.N. Secretary General Kofi Annan, who was head of peacekeeping at the world body during 1994, accepted institutional and personal blame last month for not doing more to prevent the Rwandan slaughter.

Bayigamba said Rwandans would begin a full week of mourning on Wednesday during which some remains of the genocide victims will be buried in an official ceremony and flags will fly at half-mast.

"We commemorate the genocide to give honour and dignity to the victims of genocide, reflect on the past and strive to move to a better future," he said.