Gunmen suspected to be ethnic Fulani herders have killed a policeman and 19 civilians in attacks on four farming communities in Nigeria’s northeastern Adamawa state.

Gunmen suspected to be ethnic Fulani herders have killed a policeman and 19 civilians in attacks on four farming communities in Nigeria's northeastern Adamawa state, the police said Monday.

"We lost a DPO (Divisional Police Officer) and 19 civilians in his area of jurisdiction when they came under attack by Fulani herdsmen in Girei district," police spokesman Othman Abubakar told AFP.

The senior police officer with his team were "responding to a distress call from the communities under attack to restore calm following an invasion by the armed herdsmen", he said.

Local media reports gave a much higher death toll of 30 including the police officer following the raids on Sunday morning.

The herders raided Demsare, Wunamokoh, Dikajam and Taboungo farming villages in reprisals following an earlier feud between some herders and farmers over destruction of farm crops, Abubakar said.

The villages are in Girei municipality, less than 20 kilometers (12 miles) from state capital Yola.