A Rwandan man accused of taking part in Rwanda's 1994 genocide pleaded not guilty on Monday at the opening of a war crimes trial in the Canadian province of Quebec, Montreal.
Desire Munyaneza is the first person to stand trial in Canada under its Crimes Against Humanity and War Crimes act passed in 2000.
The Quebec high court heard testimony from a young woman who says she saw some of the killing.
Prosecutors accuse Munyaneza of raping and killing civilians in Butare in southern Rwanda. In 1994, Hutu extremists killed about 800,000 ethnic Tutsis and politically moderate Hutus.
Munyaneza arrived in Canada a decade ago to seek asylum. Canada rejected his request because it suspected he was involved with the genocide. He was arrested in 2005.
Retired Canadian General Romeo Dallaire, who was with the United Nations peacekeeping force in Rwanda, also is expected to testify against Munyaneza.