Jos, Nigeria (CNN) -- An Islamic militant group in northern Nigeria has claimed responsibility for attacks that killed at least 25 people in a rash of violence against the country's minority Christians, officials said, after it issued an earlier ultimatum that gave Christians three days to leave the area. Gunmen opened fire on residents Friday, killing at least 15 people who were mourning the deaths of two slain businessmen, said Rev. Paul Alhamdu, chairman of the Christian Association of Nigeria. At least eight people were also killed on Thursday in a church shooting in northeastern Nigeria, a pastor at the church said, as sectarian violence spirals and the country is shaken by angry protests over fuel subsidies.
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Sectarian violence and fuel policy protests are tests for the president, an analyst says
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Gunmen attacked the Deeper Life church in Gombe as worshipers met for a service
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An eyewitness describes how people were gunned down as they tried to flee
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An Islamist militant group, Boko Haram, has been blamed for other attacks on churches
The church targeted in Gombe is attended predominantly by @placeholder from southern Nigeria.