Suspected Boko Haram fighters have killed dozens of people, including many children, in a massacre in the northeastern Nigeria village of Njaba, security sources and witnesses have said.

The Reuters news agency cited security forces as saying that at least 45 people were killed by members of the armed group in Borno state, while the AFP news agency reported a higher toll of 68 people.

"I participated in the counting of dead bodies. Sixty-eight people were killed," witness Muminu Haruna told AFP after escaping the attack on Tuesday in the remote region.

Children were deliberately targeted for slaughter and most of Njaba was destroyed by fire, Haruna and three others said.

"The attack was not immediately known because the village is very remote and our men couldn't access the area," a military source said told the Reuters news agency.

Njaba is close to the town of Damboa and about 100km south of the state capital Maiduguri.

Northeastern Nigeria has been the centre of Boko Haram's conflict with the government since the armed group was founded in Maiduguri in 2002.

The military, backed by regional African forces, have in recent months sought to regain territory lost to the fighters.

The government has also postponed national elections by six weeks until March 28 to buy time in its efforts to bring more stability to the troubled region.

Source: Al Jazeera and agencies