(LAGOS, Nigeria) — Nigeria's government has largely ignored years of "mass murder" in two central states, Human Rights Watch charged Thursday, failing to prosecute known perpetrators who have burned victims alive and hacked and shot to death others because of their tribe or religion. The New York-based advocacy group presented a new report in Nigeria with details of "horrific sectarian violence" that has left more than 3,000 dead since 2010 in Plateau and Kaduna, states along Nigeria's 10th Parallel where Christianity and Islam meet and often clash. In the absence of justice, people have taken to revenge killings, further fueling the cycle of violence, the organization said. Nigeria's government did not immediately respond to requests for comment and routinely ignores such reports. Human Rights Watch warned that Islamic militants waging an uprising in northeastern Nigeria have "invoked the lack of justice for attacks on Muslims" in these communities to justify killing Christians, including suicide bomb attacks on church services in Plateau and Kaduna states that killed dozens and sparked renewed sectarian clashes. Violence in the area is rooted in religion, tribe, politics and a competition for land and water resources complicated by politicians who side with their religious or tribal group, leaving others feeling aggrieved. It involves sedentary farmers who are mainly Christians and semi-nomadic Fulani cattle herders who are mainly Muslim. A violent incident could begin when a farmer steals or kills cattle that damage his crops. Then it could escalate when herders attack his village. It could be perpetuated when Christians retaliate by raiding a Muslim neighborhood. The Human Rights Watch report of more than 100 pages carries testimony from more than 180 witnesses and victims as well as police investigators, prosecutors, defense lawyers, judges, and community leaders, along with observations from the group's researchers. They visited villages that have been "ethnically cleansed" of Fulani people in attacks apparently orchestrated by Christians in the past year. In most cases, police round up hundreds at the scene of an attack, fail to take statements, hold them for a few(http://stats.wordpress.com/b.gif?host=world.time.com&blog=19871253&post=122522&subd=timeglobalspin&ref=&feed=1)