Olu Ajayi / AP

People gather outside a church following a blast in Kaduna, Nigeria, Sunday.

KADUNA, Nigeria - At least 52 people were killed in religious rioting sparked by three suicide bombings against churches in northern Nigeria, where the dead were piled up on Monday in mortuaries and cemeteries in the city of Kaduna.

Rioting broke out Sunday after suicide car bombers attacked three churches in northern Nigeria, killing at least 19 people and wounding dozens.

Christian youths had set up roadblocks and dragged Muslims from cars or motorbikes and killed them, witnesses said.

Although there has been no immediate claim of responsibility for Sunday's church bombings, Islamist sect Boko Haram, which is waging an insurgency in the northeast against President Goodluck Jonathan's government, had claimed deadly church attacks on the previous two Sundays, as well as others.

A Reuters reporter visited two hospitals in Kaduna. At the St Gerald Hospital, spokesman Sunday Aliyu said there were 40 bodies in the hospital morgue and 72 people being treated for burns and other wounds. At Barau Dikko Hospital, Matron Hassana Garba confirmed 12 dead and two injured people being treated.

"Many of [the injured] need surgery, but a shortage of blood is stalling treatment," a Red Cross official in Kaduna told the Agence France-Presse news agency.

'Explosions and gunshots'
On Monday evening residents reported gunfire and explosions in Damaturu, the capital of northeast Yobe state and the site of several previous attacks by Boko Haram.

"We are all indoors, the explosions and gunshots have been going on since 5pm. It's boom, boom, boom, everywhere," Oluchi Jonah, a local resident, told Reuters by phone.

Blasts hit northern Nigeria churches

In November, 65 people were killed in attacks claimed by Boko Haram on churches, mosques and police stations in Damaturu, where security forces often clash with Islamists in gun battles.

Corpses littered church grounds in parts of Kaduna on Monday. They were piled one on top of the other in an old cemetery, some charred.

A 24-hour curfew imposed by the Kaduna state government on Sunday largely succeeded in restoring order, residents said.

The violence stoked fears of wider sectarian conflict in Nigeria, an OPEC member and Africa's top oil producer that is home to the world's largest equal mix of Christians and Muslims.

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Mohammed Inuwa said he was lucky to escape with his life. He hid in a bush when rampaging Christian youths pulled Muslims off their motorcycles and beat them to death.

"They were mostly killing okada riders (motorbike taxis). I was hiding in the bush while all this was going on. If they saw me, that would be it," the second-hand clothes seller said, estimating 15 people were killed right by where he was hiding.

Boko Haram church bombings seem calculated to trigger wider sectarian strife, often striking at the heart of Nigeria's volatile "Middle Belt", where the mostly Christian south and Muslim north meet.

The Islamists' leader, Abubakar Shekau, has said the attacks on Christians were in revenge for the killings of Muslims.

But such attacks have usually failed to spark sustained conflict in a nation whose Muslims and Christians mostly co-exist peacefully, despite periodic flare-ups of sectarian violence since independence from Britain in 1960. 

Reuters contributed to this report.

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