A car bomb ripped through the United Nations' headquarters in the Nigerian capital of Abuja, killing at least 10 people, security sources and witnesses said.
They said the car rammed into the office building before exploding in an attack similar a June assault on the Abuja police headquarters claimed by Boko Haram, a Nigerian radical Islamist sect.
"We have had 10 dead and there could be more," said a medical official who declined to give his name.
The U.N. building was blackened from top to bottom and the remains of a car had fallen into the basement. Soldiers, firefighters and rescue workers swarmed over the area.
An Abuja-based security source said he suspected the attack was carried out by a Nigerian Islamist group, whose strikes have been growing in intensity and spreading further afield, or the North African arm of al Qaeda.
"This is very likely the work of Boko Haram and, or, AQIM (al Qaeda in the Islamic Maghreb) and is a serious escalation in the security situation in Nigeria," the security source said. "This is the worst thing that could have happened."
This year's presidential election in Nigeria was seen as the fairest since the end of military rule but it left Africa's most populous country starkly divided between the mostly Muslim north and the largely Christian south.
Militant attacks in the oil-producing regions of the south have subsided but the north has been hit by a round of bombings and killings by Islamist extremists, prompting fears violence could spread.
City A.M. Reporter