KEY POINTS:
Rwanda expelled the German ambassador and its President declared that Germany violated his country's sovereignty when it arrested one of his aides in connection with an attack that set off Rwanda's 1994 genocide.
In response, Germany asked the Rwandan ambassador to leave Berlin.
Rose Kabuye, chief of protocol for Rwandan President Paul Kagame, was arrested on Monday at Frankfurt International Airport on a warrant from France, where she is wanted in connection with the fatal April 1994 attack on the plane of former Rwandan President Juvenal Habyarimana.
French authorities, who are investigating the attack because Habyarimana's two pilots were French, suspect that Kabuye housed the Tutsi commando unit blamed for shooting down the plane.
Kabuye's lawyer, Lef Forster, said she denied involvement.
