At least 30 people have been killed and several others injured in Nigeria's central Plateau state in a series of attacks around Mangu town, despite a curfew imposed by the state government, a community spokesperson said.

Farmer-herder attacks and communal conflicts are rife in central Nigeria, an ethnically and religiously diverse hinterland known as the 'Middle Belt' where a circle of violence has claimed hundreds of lives in recent years.

The latest violence on Tuesday and Wednesday came after a Christmas Day attack in the area which left at least 140 people dead. A dusk-to-dawn curfew was imposed on Jan. 23.

The attackers targeted several villages including Kwahaslalek, Kinat and Mairana, located on the borders of Mangu and Barkin Ladi local government areas, said Joseph Gwankat, head of the community group Mwaghavul Development Association (MDA).

"The victims had sought refuge in the house of a community leader after earlier unrest in Mangu town. The attackers surrounded the house and killed those inside," Gwankat told Reuters by phone.

Survivors reported that the gunmen indiscriminately shot at people, including women and children, and set fire to houses and property.

In a subsequent statement, the MDA blamed the attack on herders, and questioned why troops deployed by the federal government to the area since the Christmas attacks didn't intervene to stop the violence.

Nigeria defence spokesperson Tukur Gusau said the military remains neutral following allegations of partisanship in the conflict, adding that troops responded professionally and by the rules of engagement.

"They have successfully arrested criminals involved in looting and burning of properties, as well as recovered weapons," Gusau said in a statement on Thursday.

The latest attacks come amid a surge in violence in the Plateau, which has seen repeated clashes between nomadic herders and local farming communities.

Plateau governor Caleb Mutfwang condemned the attacks and called for calm as his government "is taking proactive measures to halt further destruction of lives and property," his said office on Thursday.