Nigeria imposed a dusk to dawn curfew on Sunday in central Plateau state after over 100 were feared killed in communal clashes between farmers and herdsmen over the weekend. Witnesses said over 100 people have died so far but the police confirmed only 11 persons dead.

Strife in the decades-old conflict has escalated sharply this year, particularly in the ethnically and religiously diverse hinterland states known as the Middle Belt, causing more deaths than the Boko Haram insurgency in Nigeria’s northeast.

“The government has enforced a curfew from 6 p.m. to 6 a.m. in order to bring normalcy, (and) police and other security operatives have been put on alert at the moment,” Plateau State’s Commissioner of Information Yakubu Dati told Reuters.

Communal violence between herders and farmers, which originated partly over dwindling fertile land, has spiralled into a cycle of violence and reprisal attacks that has killed hundreds of people this year in the Middle Belt.

Insecurity has become a major electoral problem for President Muhammadu Buhari, who plans to seek re-election in February and who won power on pledges to deliver peace and stability.

“This further strengthens my constant call for an overhaul of the entire security apparatus of this country,” Yakubu Dogara, the leader of Nigeria’s lower house of parliament, said in a statement on Sunday.

“It just isn’t working,” he said, adding that the violence posed a serious threat to Nigeria’s democracy.

Buhari’s party rejects criticism that his administration is soft-peddling justice for the herders, who belong to the same Fulani ethnic group as the president.