Islamist fighters from Boko Haram killed at least 2,053 civilians in Nigeria during an estimated 95 attacks it calls a religious war in the first half of 2014, Human Rights Watch has reported.
"Boko Haram is effectively waging war on the people of northeastern Nigeria at a staggering human cost," said Corinne Dufka, West Africa director at Human Rights Watch on July 15.
"Atrocities committed as part of a widespread attack on civilians are crimes against humanity, for which those responsible need to be held to account."
The group has been quoted as saying it is waging a religious war and it hates the modern education system, singling out churches and schools in many of its attacks as well as other Muslims in Nigeria.
Much of its violent campaign in carried out in Borno South, a region of Nigeria's north eastern state of Borno.
Christian Solidarity Worldwide quotes Boko Haram leader Abubakar Shekau in a 2012 video, "This war is not political. It is religious. It is between Muslims and unbelievers (arna).
"It will stop when Islamic religion is the determinant in governance in Nigeria or, in the alternative, when all fighters are annihilated and no one is left to continue the fight."
Jacob Zenn, an analyst of African and Eurasian Affairs at The Jamestown Foundation wrote, "Boko Haram's ideology draws on Islamic scholars such as the 'fathers of Salafism' Ibn Taymiyyah and Ibn Wahhab, the thought leaders of the Egyptian Muslim Brotherhood Sayyid Qutb and Hassan al-Banna, and contemporary jihadists such as Osama bin Laden and Abu Musab al-Zarqawi."
He said in an articles carried by the Tony Blair Foundation that Boko Haram draws, "ideological legitimacy from the Quran and Islamic scholars, a large pool of barely literate recruits are easily indoctrinated."
Zenn notes that "despite Boko Haram's Salafist proclamation many of its foot soldiers reportedly use drugs, charms and amulets and have low levels of religious education."
He adds, "They teach that 'jihad' only means Holy War."
Mervyn Thomas, chief executive of Christian Solidarity Worldwide said, "The people of Borno South have a right to live, worship and vote without fear or repercussion.
"The persistent, violent and deliberate targeting of these communities on the basis of religion and political orientation must amount to a crime against humanity.
"The Nigerian government must ensure adequate protection of these vulnerable citizens and address and allay their concerns regarding the conduct of elements within the armed forces."
In one of the latest reported incidents, suspected Boko Haram gunmen killed at least 27 residents and set ablaze three churches during an attack on a north Nigerian village, Open Doors, which monitors Christian persecution, said Wednesday.
The attack took place around 6 a.m. July 14 in the predominantly Christian village of Dille, in southern Borno State, said Open Doors.
In early July at least 30 worshipers were killed and four churches were burned on Sunday in a village near Chibok in Northern Nigeria.
The group torched the Protestant Church of Christ in Nigeria, the Pentecostal Deeper Life Bible Church, and Ekklesiyar Yan'uwa (Church of the Brethren), among others, the Washington Times reported.
Local resident blamed Boko Haram for the incident. Boko Haram is known for its terrorising actions and as well as attacking Muslims who oppose its extremism it hits churches, schools, and police stations.
It is also responsible for the April kidnapping of more than 200 Nigerian girls most of whom are still missing.
"They killed dozens of people and burned houses after attacking worshippers," survivor Mallam Yahi told The Associated Press.
Yahi revealed that the attackers went to neighboring Kautikari, about four miles (seven kilometers) from Chibok, where they killed villagers and burned down homes. The death toll in Kautikari remains unknown.
Residents were angry at the army's slow response. They said that the soldiers refused to confront the extremists directly, shooting at them from outside the village.