A German court on Tuesday sentenced a former Rwandan mayor to life in prison, convicting him after a second trial of participating in genocide for helping organize the killing of some 400 members of the Tutsi minority in 1994.

Onesphore Rwabukombe, 58, was convicted in 2014 of being an accessory to genocide and sentenced to 14 years in prison. Both sides appealed that ruling, and a federal court found that evidence heard at the original three-year trial suggested there was sufficient evidence for a tougher conviction.

It ordered the Frankfurt state court to reconsider the case, and judges ruled Tuesday after a five-day trial. Their finding of aggravated circumstances means that early release, which is common in Germany, is less likely.

Rwabukombe, a member of the Hutu majority who was mayor of Muvumba, was accused of ordering the attack at church grounds where the victims had taken refuge in the town of Kiziguro on April 11, 1994.

Rwabukombe denies having been at the site of the killings. However, the Frankfurt court found that he “knowingly and willingly, along with other authorities, prepared, organized, commanded and set in motion the massacre.”

The defendant, it said, “sought to accelerate and conclude the events — even when he himself was in danger from the advance of opposing troops.”

Rwabukombe, who sought asylum in Germany in 2002, was arrested in 2010 on an international warrant and has been in custody since then. He wasn’t extradited after authorities concluded he couldn’t receive a fair trial in Rwanda.

More than 800,000 ethnic Tutsis and moderate Hutus were killed in Rwanda’s 1994 genocide.