Police and residents say at least 30 passengers on a bus in Nigeria’s Sokoto state were burnt to death when gunmen torched it on Tuesday.

The latest incident is a reminder of the growing insecurity in this oil producing country.

In the past, gunmen, known locally as bandits, have carried out violent attacks targeting villagers and commuters travelling on highways and kidnapped hundreds of school children for ransom in the north of the country.

Northwestern Borno state police spokesman Sanusi Abubakar said the bus was carrying 24 passengers when it was set alight by armed men and that seven people had escaped with injuries and taken to hospital.

But two residents who reached the scene and helped retrieve bodies told Reuters that the bus was overloaded and the bodies were burnt beyond recognition.

They counted body parts of at least 30 people, including women and children.

The residents said the villagers were ambushed on a road linking the Sabon Birni local government area and the village of Gidan Bawa in Borno state.