A brazen attack on the United Nations’ offices in the Nigerian capital of Abuja claimed the lives of at least 18 people on Friday.

A car laden with explosives rammed through two gates at the compound. The bomber inside the vehicle then crashed into the main reception area and detonated the explosives. The blast flattened one entire wing of the three-story building.

“This was an assault on those who devote their lives to helping others,” Secretary-General Ban Ki-moon said. “We condemn this terrible act, utterly.”

Although no group has claimed responsibility for the attack, a number of bombings have recently been carried out in Nigeria by a radical Islamic sect called Boko Haram. The group, whose name means “non-Islamic education is a sin,” attacked a police station and banks in a northeastern town on Thursday, killing 12 people.

[Reuters]