PARIS - Two former Rwandan mayors went on trial Tuesday in Paris for allegedly inciting and taking a leading part in the mass killing of ethnic Tutsis during the first days of the 1994 Rwandan genocide.

Tite Barahirwa, 64, and Octavien Ngenzi, 58, are both accused of genocide and crimes against humanity over the massacre of some 2,000 Tutsis who had sought refuge in a church in the eastern town of Kabarondo.

The men, who deny any involvement in the murders, face up to life in prison if convicted.

More than 100 victims, relatives and witnesses, some of whom travelled from Rwanda, are expected to testify during the eight-week Paris trial. Unusually, it is being recorded for historical purposes.

This trial is the second held in France for suspected perpetrators of the Rwandan genocide, under a special U.N.-approved law allowing France universal jurisdiction for related crimes. The law came after years of efforts for justice by activist groups who say France — close to the Hutu leadership of Rwanda at the time — turned a blind eye to the slaughter and allowed perpetrators to live in France unpunished.

Some 800,000 people, mostly ethnic Tutsis, were killed by Hutu extremists during the three months of the Rwandan genocide in spring 1994, according to U.N. figures.

Barahirwa and Ngenzi were arrested separately in French territory a few years ago and have been held in custody since then.

The first attacks against ethnic Tutsis by rival Hutus in the Kabarondo sector started the day after then-Rwandan President Juvenal Habyarimana died when his plane was shot down on April 6, 1994. In the following days, a growing number of Tutsis and some Hutus sought refuge in the town church and some 3,500 were inside the day before it was attacked.

On the morning of April 13, Barahirwa allegedly held a meeting in a nearby soccer stadium where local armed Hutus were ordered to "chase and kill ethnic Tutsis" throughout the town and especially at the church, except Tutsi women married to Hutu men, according to witnesses quoted in court documents.

Shortly after the meeting, a few hundred militiamen armed with machetes, spears, arrows and bows, bludgeons and studded clubs attacked the church. Then Rwandan armed forces arrived and used more powerful weapons against the people inside: mortars, bombs, grenades.

"Shells were entering the church through the windows and roof, digging holes in the ground. Some people had their limbs torn apart," witness Jovithe Ryaka told investigators. "People were falling again and again," another witness, Jean-Bosco Muberuka, was quoted as saying in court documents.

Once the church door was smashed open, militiamen and soldiers entered the church to finish the wounded off with machetes and clubs and take those still alive outside. Witnesses said Barahirwa and Ngenzi were present at that time, conducting an "ethnic selection" of the survivors, executing those identified as Tutsis. Barahirwa is accused of killing some of them himself.

Barahirwa and Ngenzi are both accused of "taking part in a widespread and systematic practice of summary executions, inspired by political, philosophical, racial or religious reasons and organized in execution of a concerted plan against a civilian population group, in this case the civilian Tutsi population."

In the first such trial in France, in 2014, Pascal Simbikangwa, a former head of the Rwandan intelligence service, was convicted of genocide and complicity of crimes against humanity and sentenced to 25 years in prison. He has appealed the verdict.

News from © The Associated Press, 2016