Bloody day in Nigeria, Boko Haram also attacked two police stations and two banks killing at least 12.

ABUJA, Nigeria (AP) — A car laden with explosives detonated outside the United Nations’ main office in Nigeria’s capital Friday, blowing part of the concrete structure into shards and killing at least seven people.

A U.N. official in Geneva confirmed to CBS News that it was a bomb attack, and a Nigerian security official told Reuters news agency it was the result of a car bomb.

Witnesses told The Associated Press that a sedan broke through the exit at the U.N. compound, ramming through two separate gates as guards tried to stop the vehicle. The suicide bomber inside drove the car just up to the main reception of the building before detonating, inflicting the most damage possible, witnesses said.

“I saw scattered bodies,” said Michael Ofilaje, a UNICEF worker at the building. “Many people are dead.”

Nigeria, a nation of 150 million, is split between a largely Christian south and Muslim north. In recent months, the country has faced an increasing threat from a radical Muslim sect called Boko Haram, which wants to implement a strict version of Shariah law in the nation. The sect has carried out assassinations and bombings, including the June car bombing of the national headquarters of Nigeria’s federal police that killed at least two people.

Earlier this month, the commander for U.S. military operations in Africa said Boko Haram may be trying to link with two al-Qaida-linked groups in other African countries to mount joint attacks in Nigeria.

Gen. Carter Ham told AP on Aug. 17 during a visit to Nigeria that “multiple sources” indicate Boko Haram made contacts with al-Qaida in the Islamic Maghreb, which operates in northwest Africa, and with al-Shabab in Somalia.

Update: As expected.

(Guardian) — Nigeria’s capital was on high alert on after an apparent suicide attack on the United Nations headquarters in Abuja stoked fears that Islamist militants were setting their sights on high-profile targets in Africa’s most populous country.

The car bomb – the first attack on the UN in Nigeria — ripped through the heavily fortified UN building, killing at least 18 people. Describing those who carried out the apparent suicide bombing as “barbaric”, President Goodluck Jonathan ordered all relevant government agencies to help in the search and rescue effort.

“The president believes that the attack is a most despicable assault on the United Nations’ objectives of global peace and security, and the sanctity of human life to which Nigeria wholly subscribes,” the president’s office said in a statement.

The UN secretary general, Ban Ki-moon, who asked his deputy, Asha-Rose Migiro, to go to Nigeria immediately, said: “This was an assault on those who devote their lives to helping others. We condemn this terrible act, utterly.”

The Islamist group Boko Haram told the BBC in a phone call that it had carried out the attack. If the claim turns out to be genuine, the attack would confirm American fears that al-Qaida-affiliated groups are targeting the important west African state.

Witnesses said a car rammed through two separate gates at the UN compound as guards tried to stop it. The suicide bomber drove up to the main reception area before blowing himself up.