The explosions rocked two churches in Wusasa and Sabon Gari, Zaria and Tirkaniya in Kaduna.
The Zaria attacks appear to have been coordinated as they happened simultaneously at ECWA Church in Sabon Gari and Christ the King Cathedral Church in Wusasa.
The suicide bombers drove cars rigged with explosives to the churches and detonated them.
The ECWA bomber dressed like a woman and infiltrated the church.
A gunfight broke out between security agents and suspected terrorists after the blasts.
Rescue officers rushed to the scenes of the blasts although the casualties were not known.
Shortly after these blasts, a third was reported at Shalom Royal International Church in Tirkaniya area of Kaduna.
The spokesman for the National Emergency Management Agency, Yushau Shuaibu, confirmed the incidents, saying rescue officers were moving the dead and injured to the hospitals.
Rioting broke out in parts of the state capital after the blasts, as hundreds of angry youths rioted in Gonin Gora near Kaduna-Abuja Expressway; Sabon Tasha; Television; Narayi; and Ungwan Romi.
They burnt cars and attacked persons suspected to be Hausa-Fulani.
About 11 persons were killed in reprisal attacks.
Many Hausa-Fulani were rescued by soldiers and policemen. A number of them took refuge at Kaduna Mobile Police Barracks while a military helicopter hovered around the city.
The state government imposed a 24-hour curfew on the state to curtail further violence.
Wusasa is the site of the first church to be built in Northern Nigeria.
Recently, hardly any Sunday goes by without a church being attacked in Northern Nigeria.
Gun and bomb attacks on a church in Jos, the Plateau State capital, and Biu in Borno State last Sunday claimdd about 10 lives.
The attacks were claimed by the Boko Haram sect.
More details later.