The site of a car bomb explosion outside a church in Kaduna on April 8, 2012.
In Nigeria, multiple blasts targeting churches in neighboring cities of the northern Kaduna State have claimed dozens of lives.
Local officials say a church has been struck in Kaduna city minutes after two other churches were bombed in Zaria.
Authorities in the country's north have imposed a 24-hour curfew on the area.
Although no official reports on the exact number of injuries or casualties have been made, locals say dozens have been wounded in the blasts.
No group has yet claimed responsibility for the attacks.
On Friday, the Nigerian military’s Joint Task Force killed four members of the Boko Haram militant group during a raid on one of the group’s hideouts in the northern city of Kano.
Also last Sunday, at least six people were killed when the attackers bombed a church in the central Nigerian city of Jos and another church in the northeastern state of Borno.
Nigeria has been witnessing growing instances of sectarian violence.
The extremist group has claimed responsibility for a number of deadly gun and bomb attacks in various parts of Nigeria since 2009.
Human rights groups report that violent actions by Boko Haram since mid-2009 have claimed more than 1,000 lives, including over 300 this year alone.