The prosecutor of the International Criminal Court condemns the escalation in "appalling levels" of violence in Nigeria's northeastern Islamic uprising and warns she will prosecute members of any party to the conflict most responsible for war crimes and crimes against humanity.

A statement Tuesday from Fatou Bensouda says her office is continuing to investigate allegations Boko Haram extremists are killing large numbers of civilians, using girls and boys to participate in the conflict and forcing massive numbers of people from their homes.

She also warns the government of Nigeria of its obligation to prosecute crimes that "deeply shock the conscience of humanity."

Both Boko Haram and the Nigerian military are accused of summary executions of civilians in the 5-year uprising that killed more than 10,000 people last year.