There was no immediate claim of responsibility for Sunday's attack, but a radical Islamist sect known as Boko Haram has previously targeted churches and the military.
Twin car bombs hit a Protestant church in a major military establishment in north-central Nigeria, officials said Sunday, a month after a church bombing in the same state killed at least seven people and injured more than a hundred others.
The first explosion occurred after a church service Sunday in a military barracks in Jaji town in Kaduna state, said National Emergency Management Agency spokesman Yushau Shuaib.
A second blast occurred just outside the church minutes later at about 1 p.m., said a medic who required anonymity because she is not authorized to speak to the press. She said the church targeted was a Protestant church.
Shuaib said the casualties are not yet known.
Police spokesman Aminu Lawan declined to comment, saying that it was a military matter. A military spokesman could not immediately be reached for comment.
Civilian authorities in Nigeria are generally reluctant to comment on military affairs. But Jaji is a symbolic target as it is home to the Armed Forces Command and Staff College, one of the country's most important military colleges, training Nigerian and foreign navy, air force, and army officers.