Updated

The prosecutor of the International Criminal Court says that after a preliminary investigation she believes that acts attributed to the Nigerian Islamist group Boko Haram are likely crimes against humanity.

Fatou Bensouda says the acts include murder and persecution. But she will only move to a full-fledged investigation after further study and depending on whether Nigerian authorities prosecute "those who appear to bear the greatest responsibility."

Her report issued Monday in The Hague, Netherlands, is based on evidence gathered through December 2012.

Boko Haram operates in the Northeast of Nigeria.

Nigeria declared a state of emergency on May 14 to fight an Islamic uprising by militants in the northeast who want to impose Islamic law across a country divided almost equally between the predominantly Muslim north and mainly Christian south.