Police in central Nigeria's Plateau state say nine people have been arrested in connection with renewed attacks in the Mangu area.

At least 50 people are reported to have been killed in two days of communal clashes.

Villages near Mangu town were targeted by armed men on Wednesday, a day after mosques and churches were set on fire during confrontations between two rival ethnic groups.

A spokesman for the Nigerian military, General Edward Buba, said special forces had been deployed to hot spots in the state to contain the situation.