A damaged crucifix overlooks the scene of a bomb explosion at St. Theresa Catholic Church at Madalla
Boko Haram has attacked several churches

Gunmen have attacked a church and killed at least 19 people including the pastor in central Nigeria.

Armed with Kalashnikov assault rifles, the assailants stormed the church in Kogi state, near the city of Okene, during a service.

The joint military force commander in Kogi state, Lt Col Gabriel Olorunyomi, said the gunmen targeted the Deeper Life Bible Church in the town of Otite, near Okene, the AP news agency reports.

It is not clear how many people were injured.

Witnesses said blood covered the church floor.

Soldiers searched the church and nearby areas but no arrests were made. No group claimed responsibility.

The attack comes amid a growing insurgency by the Islamist group Boko Haram in the north of Nigeria, which has targeted churches, schools, police stations and state institutions. The latest assault surprised security forces because Otite is in the south.

The group wants Sharia law imposed over the country and has criticised the country's federal government for failing to tackle endemic corruption.

In a video released online the group's leader Abubakar Shekau insisted the sect would not hold talks with government officials and reiterated calls for President Goodluck Jonathan to step down.

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