"The failure of the government to properly equip and train the police reduces their ability to ensure their own and other people's safety. Hundreds of police, military and SSS (State Security Service) have been killed by Boko Haram since 2009. They have been shot and blown up in their stations, at roadblocks and in their homes," the report said.

The rights group makes a series of recommendations, with specific points addressed to President Goodluck Jonathan, the ministries of defense and justice as well as the police, security services and lawmakers.

They include strengthening systems and training to ensure abuses are not carried out by security forces, and greater efforts to investigate abuse allegations and ensure the safety of witnesses.

Nigeria has almost equal numbers of Christian and Muslims, with the south predominantly Christian. Boko Haram and other Muslim groups claim the north has been starved of resources and marginalized by the government of Jonathan, a Christian.

From its base in Muslim-dominated northern Nigeria, Boko Haram, which has referred to itself as the "Nigerian Taliban," has waged a violent campaign of bombings of Christian churches that have killed hundreds and wounded many more. There have been fewer attacks by Christian militant groups.