US officials extradited a Rwandan woman convicted in absentia by a court in her country for her role in the 1994 genocide, an official said Thursday.

Marie-Claire Mukeshimana was brought to Kigali late on Wednesday. She was sentenced in 2009 to 19 years in prison for complicity in the killing of several children who had sought refuge at a convent in southern Rwanda.

Rwanda's chief prosecutor Martin Ngoga welcomed the extradition.

"But we have a number of more identified persons who stand accused of genocide committed in the most brutal manner and claiming so many lives, who remain on US territory," he told AFP.

"We have a strong feeling that action against them is very slow."

An estimated 800,000 people, mostly minority Tutsis, were killed in the genocide.

Mukeshimana, 43, lived in the US city of Detroit after fleeing Rwanda.

She is the second genocide convict to be returned to Kigali this year by US authorities, who in January extradited a man convicted over the genocide.