At least 18 people were killed at a U.N. base in Abuja, Nigeria on Friday when a suicide bomber drove a vehicle packed with explosives into the headquarters.

U.N. Secretary-General Ban Ki-moon has since condemned the morning attack and said top officials will be dispatched to the Nigerian capital to respond to the emergency.

The compound in Abuja is a series of buildings that is home to the offices of 26 U.N. humanitarian and development agencies. It was struck by a car bomb at around 11 a.m. local time. The U.N. said hundreds of staff members were working in the compound at the time of the attack.

This was an assault on those who devote their lives to helping others, Ban said at U.N. Headquarters in New York. We condemn this terrible act, utterly.

He added that the U.N. will undertake every possible effort to assist victims and their families during this difficult time.

In the meantime, Nigerian and international search and rescue teams have already been mobilized and are moving the wounded to hospitals and providing emergency aid.

The have been reports that the recent attack has increased fears that a local Islamist militant group inspired by the Taliban may be widening its terror attacks to include Western targets.

And Boko Haram, a radical Islamist sect, has claimed responsibility for the attack, which is said to be the most serious carried out by the group that is based in Nigeria's Muslim majority north, according to the Los Angeles Times.

Some people believe the group is forging ties with al Qaeda, the Times report stated.

More attacks are on the way, and by the will of Allah we will have unfettered access to wherever we want to attack, spokesman Abu Darda, said by phone, to the Times. We have more than 100 men who are willing to lay down their lives for the cause of Allah.

U.N. spokesman Farhan Haq has said there wasn't any previous threat against the U.N. compound. The compound had barriers around it to protect against attack.

It is regarded as a well-defended building and we will need to investigate how it was that the attackers managed to get past different levels of protection so that they could cause the damage that they did, he said, as reported by the U.N.'s Web site.