Nigerian officials say a car bombing near a church on Easter Sunday killed at least 20 people in the country's north.

A witness said the bomb went off in a business area near the church in the north Nigerian town of Kaduna.

There was no immediate claim of responsibility.

The explosion follows warnings by foreign diplomats of possible attacks on one of the biggest Christian observances of the year.

Nigeria was also hit by four bombings on Christmas that killed at least 44 people, including dozens at a Catholic church near the capital, Abuja. The radical Islamic group Boko Haram claimed responsibility for what appeared to have been coordinated attacks.