(CNN) -- A Nigerian militant group has claimed responsibility after a car loaded with explosives rammed into the United Nations' building in the capital, killing 23, a government spokesman said Monday. The suicide attack Friday shattered windows, set the building ablaze and left gaping holes on the walls. Radical Muslim sect Boko Haram, which aims to enforce a strict version of Sharia law, has claimed responsibility, said Reuben Abati, the government spokesman. Eighty-one people were injured, he said. The attack targeted a building that housed 26 U.N. humanitarian and development agencies, U.N. Secretary-General Ban Ki-moon said last week. The Liberian and U.S. embassies are also nearby.
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Boko Haram claims responsibility for the blast
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Nigeria's president says the bombing was "barbaric, senseless and cowardly"
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The capital has suffered a series of bombings in recent months
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Ban: "This was an assault on those who devote their lives to helping others"
The group holds all government authority in contempt and wants to establish a @placeholder state in northern Nigeria.