Plateau State, Nigeria (CNN) -- Gunmen attacked a mosque in Nigeria with automatic weapons over the weekend, killing at least 44 people, a local police official said. It's not clear who was behind Sunday's massacre, but the militant Islamist group Boko Haram -- which has staged attacks in the same region before -- issued a video around the same time boasting that it was gaining in strength. Details have been slow to emerge about the attack in Konduga, about 30 kilometers (almost 19 miles) southeast of Maiduguri, the capital of Nigeria's northern Borno state. The police official in Konduga spoke to CNN on condition of anonymity because he is not authorized to speak to the media.
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NEW: 26 people were injured in the mosque attack in Borno state, a medical source says
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At least 44 people died when gunmen attacked the mosque, a police official says
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Villagers have also been attacked for helping the government, police sources say
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Boko Haram leader released a video over the weekend, boasted of the group's strength
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