“The crimes occurred after we requested the arrest of Mbarushimana, but now we are trying to see whether we can add these crimes to the list of crimes he is charged with,” the prosecutor told France 24 television.
Mbarushimana, wanted by the ICC for war crimes and crimes against humanity in the eastern DR Congo was arrested in France last Monday for crimes committed in 2009.
Prosecutors had obtained an arrest warrant in September on five charges of crimes against humanity and six war crimes, including for murder, rape, torture and destruction of property.
Mbarushimana, 47, has been living in Paris as the leader-in-exile of the Rwandan rebel group, the Democratic Forces for the Liberation of Rwanda (FDLR).
The United Nations says a coalition of at least 200 fighters from the Mai-Mai militia and the FDLR raped some 500 men, women and children in 13 villages in the Walikale region of DR Congo in late July and early August.
In August, Mbarushimana had issued a statement from Paris denying that the FDLR was involved in the commission of the rapes.
“That was one of the roles of Mbarushimana, to cover up the crimes,” said Moreno-Ocampo.
“Some of the perpetrators who are in jail say the FDLR leaders gave the order to commit those crimes.”
Moreno-Ocampo promised that Mbarushimana’s arrest “will not be the last”. “We will do more on the FDLR. We will focus on them. We will demobilise them. And if they commit this type of crime, they will go to jail.”
The prosecutor added that Mbarushimana’s arrest was “the result of a common effort” with Germany, Rwanda, the DR Congo and France, who helped to “intercept conversations” and collect information.