Amid international travel warnings of terrorist attacks in Nigeria, a report says 15 people were killed in early February in two attacks at a church in a town in the northeastern part of the nation.

At least 15 people, including eight members of a congregation were killed in two attacks against a church affiliated with the Church of the Brethren in Nigeria, according to a report published  Monday by Church of the Brethren Newsline.

The LCC Samunaka church on the outskirts of the city of Mubi in Adamawa State was attacked twice in four days, the publication reported. The attacks took place on Feb. 1 and again on Feb 4.

The report indicated that the church building and the pastor's office were burned down, along with some houses belonging to Christians.

Two other denomination churches were burned down in other areas on the same weekend, including an incident at LCC HUwin in the Mussa district on February 2, and LCC Bita in the Gavva west district on Feburary 3, a denomination report said.

The report indicated two visitors from the U.S.-based Church of the Brethren in the country for a "mini workcamp" left the country safely on February 7. The Americans who left safely were Jay Wittmeyer, executive director of Global Mission and Service, and Fern Dews of North Canton, Ohio.

The representatives delivered cards and letters of support to the Nigeria denomination, expressing encouragement from the American church in the face of continuing violence, the report states.

The American church transferred just over $30,000 to the Nigerian church's donations for a fund that helps care for churches and members affected by violence.

In light of the deployment of troops in northern Mali to counter Islamist rebels, the United Kingdom updated a travel warning for Nigeria on January 23, which it first made on January 13. The warning advised against all but essential travel for various areas in Northern Nigeria, including Mubi.

Extremist group Boko Haram, translated as "Western education is forbidden," has often claimed responsibility for attacks.

The UK indicated there is a "high threat from terrorism" in the country and that attacks could be indiscriminate, although it noted that a number of attacks have taken place around religious and public holidays.

"There have been regular attacks on churches in northern Nigeria at times of worship," the warning states. "We cannot therefore rule out further attacks taking place. You should be particularly vigilant at these times and in these locations."

A report released by the World Council of Churches and The Royal Aal al-Bayt institute for Islamic Thought released a report in July 2012 stating that the primary causes of the current tension and conflict in Nigeria are not inherently based in religion but rather, rooted in a complex matrix of political, social, ethnic, economic, and legal problems.

The report indicated that "[T]he issue of justice - or the lack of it - loom large as a common factor."

The report acknowledged that "there is a possibility that the current tension and conflict might become subsumed by its religious dimension (especially along geographical 'religious fault-lines') and so particularly warns against letting this idea-through misperception and simplification-become a self-fulfilling prediction."