A series of Christmas Eve explosions and attacks in Nigeria, several of them at churches, have killed at least 38 people.

In the northern city of Maiduguri, authorities say suspected members of the Islamist sect Boko Haram threw gasoline bombs at three churches, killing six people and leaving one of the churches burned to the ground. Among the dead was a Baptist pastor, whose house also was destroyed.

At least 80 people are now known to have died in violence around the Nigerian city of Jos in recent days.

Officials revised the death toll from about 40 after consulting hospitals.

The clashes usually pit Muslims against Christians, but analysts say the underlying issues are political and economic.