An Islamist militant group has claimed responsibility for a suicide bomb attack on the United Nations headquarters in Nigeria which killed at least 18 people.
The bomber rammed a car packed with explosives through two security barriers at the UN complex and smashed it into the building.
The building, in the capital Abuja, housed 26 UN humanitarian and development agencies, Reuters reports.
Many people were injured in Friday's attack and UN Secretary- General Ban Ki-moon says the final casualty toll is likely to be considerable.
The BBC reports that a spokesman for Islamist group Boko Haram said in a phone call that it had carried out the attack.
The group has carried out a series of attacks in Nigerian towns and cities in recent months.
Boko Haram, whose name translates from the local northern Hausa language as "Western education is sinful", has been behind almost daily bombings and shootings, mostly targeting police in the northeast of Nigeria.
The group claimed responsibility for a bomb attack on the car park of the Abuja police headquarters in June, in which a car rammed through the gates of the building exploded.