Gunmen have killed six people at a church in northeast Nigeria, the military said on Tuesday, December 25 the third year running Christmas services have come under deadly attack in Africa's most populous nation, Reuters reported.

The strike took place after a Christmas Eve midnight service outside the town of Potiskum, in northeast Yobe state, where Islamist sect Boko Haram has carried out several attacks this year, the military said.

"Unknown gunmen attempted to attack Potiskum but were repelled by the troops, while they were fleeing they attacked a church in a village known as Jiri," Military Spokesman Eli Lazarus said, confirming six people were killed.