HELSINKI (AP) — A trial has started in Finland for a Sierra Leone man charged with committing serious war crimes, including several murders, and crimes against humanity during Liberia’s bloody second civil war from 1999 through 2003.

Gibril Massaquoi, who has been living in Finland for more than 10 years, is alleged by Finnish prosecutors to have held a leading position in the Revolutionary United Front, a rebel army in Sierra Leone that was involved in the Liberian civil war in West Africa.

The mask-wearing Massaquoi, known to have used the alias “Angel Gabriel,” was present at the Pirkanmaa District Court in the southern Finnish city of Tampere where the main handling of the case started Wednesday. Finnish media reported the 51-year-old defendant didn’t say anything at the court.

Prosecutors are seeking a life sentence — which is usually around 14 years in Finland — for Massaquoi, who has denied all charges. Those charges include his alleged direct or indirect participation in rapes, murders, cannibalism and using child soldiers during the conflict in Liberia.

Massaquoi was arrested in March last year by Finland’s National Bureau of Investigation in Tampere, a main industrial and university city, where according to Finnish media reports he held a job and had a family with children.

Massaquoi is allegedly the first non-Liberian to be held accountable in connection with Liberia's brutal first and second civil wars, which are estimated to have killed at least 500,000 people. He ended up in Finland under a witness relocation scheme.

Later this month, the Finnish court, in a rare move, will temporarily relocate to Liberia and neighboring Sierra Leone to hear testimony from dozens of witnesses on the alleged atrocities carried out by Massaquoi himself or by others on his orders.

A verdict in the case is expected next fall.