Nigerian newspaper Thisday reported Monday that it obtained a preliminary report from the International Criminal Court stating Boko Haram was under investigation for militant activity.
"The office has determined that there is a reasonable basis to believe that crimes against humanity have been committed in Nigeria, namely acts of murder and persecution attributed to Boko Haram," the newspaper quoted the report as saying.
Thisday added Monday that it received reports from anonymous sources that blamed Boko Haram for an attack on a special police headquarters in Abuja. Most of the area was cordoned off after sporadic shooting. There were no reports of injury, though the newspaper adds several prisoners were able to escape during the melee.
Suspected members of Boko Haram targeted a Christian church in northern Nigeria last weekend in an attack that left at least 11 people dead. A similar attack was attributed to the Islamic sect in October.
Boko Haram aims to set up an Islamic state in Nigeria. The country is divided along Muslim and Christian lines.