Jos, Nigeria (CNN) -- A string of bombs struck churches in five Nigerian cities Sunday, leaving dozens dead and wounded on the holiday, authorities and witnesses said.

The blasts mark the second holiday season that bombs have hit Christian houses of worship in the west African nation. In a statement issued late Sunday, Nigerian President Goodluck Jonathan called the bombings "a dastardly act that must attract the rebuke of all peace-loving Nigerians."

"These acts of violence against innocent citizens are an unwarranted affront on our collective safety and freedom," Jonathan said. "Nigerians must stand as one to condemn them."

Bombs targeted churches across the country, hitting the cities of Madalla, Jos, Kano, and Damaturu and Gadaka, said journalist Hassan John, who witnessed the carnage in Jos. The death toll in Madalla alone was 18, including two people reported dead overnight at a nearby hospital, Nigeria's National Emergency Management Agency spokesman Yushau Shuaib told CNN.

John said witnesses in Madalla reported a higher death toll, with more than 30 killed. Some victims died after being taken to a hospital, he said.

In Damaturu, a northern town in Yobe state, a police station and a state security building were also bombed, an aid worker said. The worker asked not to be named for security reasons.

Nwakpa Okorie, a spokesman for the Nigerian Red Cross, said the some of the wounded were taken to the capital Abuja for treatment.

"The situation is under control now. The security agents have secured the streets close to the bombed areas ... in Madalla, Jos and Dematuru," he said.

1. How many people died in Madalla?
2. Where is Damaturu?
3. What is Nwakpa Okorie the spokesman for?
4. Is the incident still ongoing?
5. Who said it wasn't?
6. What was the building type that was targeted?
7. Who did yushau Shuaib talk to?
8. Who does he work for?
9. Where in Africa is Nigeria located?
10. Is the president mad about the incident?
11. What day did the bombings occur/
1. more than 30
2. in Yobe state
3. the Nigerian Red Cross
4. no
5. Nwakpa Okorie
6. churches
7. CNN
8. Nigeria's National Emergency Management Agency
9. in the west
10. yes
11. Sunday