Story highlights The man is tied to several massacres in western Rwanda

At least 800,000 people were killed in the 1994 genocide

The convicted man is a Swedish citizen of Hutu origin

A Swedish citizen of Rwandan origin was sentenced to life in prison Thursday by a court in Stockholm after he was tried and convicted for his role in the country's genocide nearly 20 years ago.

He is 54-year-old Stanislas Mbanenande, an ethnic Hutu. At least 800,000 people in Rwanda were killed in the 1994 genocide, one of the worst mass slaughters in the post-World War II era.

This is the first time that Sweden has tried a case for genocide, and also the first time anyone has been convicted of genocide in a Swedish court.

The victims were mostly from the Tutsi ethnic minority, who were targeted by Hutus over a rivalry that dates to colonial days. Some moderates from the Hutu majority who supported Tutsis also were killed.

Along with a charge of genocide, Mbanenande was convicted in the Stockholm District Court of gross violations of international law, including murder, attempted murder, inciting murder and kidnapping.

The case involves several massacres in western Rwanda's Kibuye prefecture, where Mbanenande was born and raised.

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Mbanenande was accused of having an informal leadership role and using an automatic weapon to shoot at groups of people. He took part in massacres at public buildings such as a church, a school and a sports stadium where people sought shelter.

He also is accused of taking part in the hunt for Tutsis in the Ruhiro and Bisesero mountains where people had fled to seek safety.

Mbanenande left Kibuye in 1994 when Tutsi-dominated invasion troops were nearing. He then lived in Congo until 1996, and then he moved to the Kenyan capital of Nairobi.

In 1999 his family moved to Sweden. Mbanenande eventually joined them and became a Swedish citizen in 2008.