Nairobi/Lagos, Dec 25 (DPA) A series of bomb attacks on Christmas eve left at least seven people dead in Nigeria, a news report said Saturday.

At least nine explosions hit different parts of Plateau State in the centre of the country within an hour of each other late Friday, the Daily Sun reported.

A police officer from state capital Jos was quoted as saying that seven people were killed. The newspaper said that other sources reported about 20 fatalities and a ‘score’ of people injured.

An unidentified group had warned that it would take measures to ensure that Christmas was not celebrated in the state, the report quoted military sources as saying.

The newspaper said its own investigations showed the first bomb exploded in front of a Catholic church.

Violence between Christian and Muslim groups in Nigeria has claimed several hundred victims this year.

Observers have said the clashes are more than religious, as the Muslims, largely nomadic herdsmen from the north of the country, come into conflict with farming Christians from the south.