Up to 10,000 people have died in Nigerian clashes in the past three years

Hundreds have fled the Mambila Plateau area of Taraba state in the past week since fighting began between the Mambila and the nomadic Fulani communities.

The area, which borders Cameroon, has a long history of competition between farmers and livestock rearers competing for scarce resources.

Correspondents say tensions have risen yet further since local government officials threatened to re-distribute land that was not being used effectively.

Nigeria has been wracked recently by its worst cycle of ethnic, religious and political bloodletting for more than 30 years.

Toll unconfirmed

The number of dead in the latest clashes is unconfirmed, but the AFP news agency put the number of casualties at more than 50.

Police reinforcements have been sent to the area from neighbouring Adamawa state to restore calm.

The Reuters news agency quoted local newspapers as saying many Fulanis had taken their livestock and fled into Cameroon.

The hilly region has in recent years seen an influx of farmers, stoking Mambila fears that the Fulanis are encroaching on their land.

The BBC's Abdullahi Tasiu Abubakar said the problem has been compounded by politicians who have used the land issue as an electoral platform to win votes.

In November, land disputes elsewhere in Taraba between the Tiv and Jukun communities left up to 50 people dead.

Up to 10,000 people are thought to have died in communal, religious and sectarian violence since the country returned to civilian rule in 1999.