Officials said at least 16 people died and dozens were injured in the blasts.

Some 20 more people were killed in later rioting apparently targeting Muslims, aid workers and witnesses said.

Kaduna state authorities have imposed a 24-hour curfew as soldiers and police try to restore order.

No-one has yet claimed responsibility for the blasts, but Kaduna state has previously seen attacks by the radical Islamist group Boko Haram.

Last week the group attacked two church services, sparking violence which killed seven people. Hundreds have died in its previous attacks on churches.