The head of Nigeria's Christians said Saturday the killing of dozens of faithful in attacks blamed on Islamists suggested "ethnic and religious cleansing" reminiscent of the start of the 1960s civil war.

Christians would "do whatever it takes" to defend themselves, Ayo Oritsejafor, head of the Christian Association of Nigeria, said after a meeting of church leaders.

More than 30 worshippers have been shot dead in northeast Nigeria since Wednesday, many while praying in churches, after the expiration of an ultimatum by an Islamist sect for Christians to leave the country's mainly Muslim north.

Oritsejafor said an emergency meeting of church heads concluded "that the pattern of these killings does suggest to us a systematic ethnic and religious cleansing."

"We are reminded by the occurrences of these killings of the genesis of the civil war that took place here in Nigeria," he added, reading from a statement prepared after the meeting in the capital Abuja.

Oritsejafor said the Christian leaders had resolved to "work out means to defend ourselves against these senseless killings.

"We have the legitimate right to defend ourselves and ... we will do whatever it takes," he added, without elaborating.

The leaders denounced the failure of state governors in the relevant areas to stop the violence.

"We hold them responsible for these heinous killings of people taking place in their states. We will not take it lightly."

Officials in Adamawa state, the scene of most of Friday's bloodshed, placed the territory under a 24-hour curfew Saturday and deployed security forces in a bid to halt the carnage.

AFP