Ten people were killed and at least 29 wounded in a blast in the city of Kaduna, said Andronicus Adeyemo, the official. Two people died and 51 were wounded in two church attacks in the nearby city of Zaria, he said, adding that the Zaria attacks occurred about 10 minutes apart in different parts of the city.
Churches increasingly have been targeted by violence in Nigeria, a nation of more than 160 million people almost equally divided between Muslims and Christians.
An Easter Day blast in Kaduna killed at least 38 people. A Christmas Day suicide bombing of a Catholic church near Abuja, the capital, killed at least 44 people.
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