"Valerie Bemeriki was arrested in north-west Rwanda late last week. She will be prosecuted for genocide and crimes against humanity," the Justice Minister, Jean de Dieu Mucyo said.
Ms Bemeriki is remembered by Rwandans for her inflammatory broadcasts on Radio Milles Collines which urged Hutus, the majority ethnic group, to slaughter ethnic Tutsis.
She is alleged to have denounced Tutsis hiding in the capital Kigali and to have directed attacks by Hutu militia on Tutsi refugee camps. Local residents recall hearing her saying repeatedly: "Do not kill those inyenzi [cockroaches] with a bullet - cut them to pieces with a machete."
Ms Bemeriki's name figures in a list of the 1,000 most-wanted Rwandans who allegedly planned and led the genocide directed against the Tutsis and any Hutus who sympathised with them. The Tutsis were the feudal rulers of Rwanda for centuries before their kingdom was overthrown in 1959.
Radio Milles Collines was launched as a private station in 1993, and members of the family of the Hutu president Juvenal Habyarimana - whose death in an air crash sparked the genocide - were shareholders. (Reuters)