ABUJA, (AFP) — A radical Islamist sect has claimed responsibility for Nigeria’s first suicide bombing, saying the attack that killed two at Abuja’s police headquarters targetted the country’s police chief.

“We are responsible for the bomb attack on the police headquarters in Abuja, which was to prove a point to all those who doubt our capability,” the group known as Boko Haram said late Thursday after the attack.

The powerful explosion ripped through the car park inside the police headquarters compound, killing a police officer and the bomber, wounding several others and destroying dozens of cars, according to police.

Local media said the death toll could be higher.

Security experts said it was the first suicide bombing in Nigeria, a country of 150 million people facing a growing threat from Islamic militants.

Boko Haram said it regretted missing its target, which it named as police inspector-general Hafiz Ringim.

In the statement signed by spokesman Abu Zaid, the group said the police chief had recently been making “unguarded utterances to the effect that he will crush us in a matter of days.”

Witnesses said the motorcade of a senior police officer had driven into the headquarters just minutes before the attack.

Police said the bomber drove into the car park and set off the bomb as he was about to be submitted to a routine search. Local media say the bomber was trailing the police chief as he drove into the compound.

Shortly after the attack, police blamed Islamists who a day earlier had threatened to step up a campaign of violence that has already seen scores of deadly attacks.

Boko Haram, sometimes called the Nigerian Taliban, had warned Wednesday of “fiercer” attacks saying it was angered by a police declaration that its days were “numbered.”

The sect, believed to be based in the northeastern city of Maiduguri, this week admitted links with a foreign Islamist group connected to Al-Qaeda, saying some of its members had just returned from training in Somalia. Security experts earlier speculated that it had established ties with Islamists in north Africa.

“We will continue to launch similar attacks on the police headquarters. We will not relent,” said the group, which has warned it will wage a “jihad” or holy war.

The explosion, the latest in a series of blasts in recent months, adds to insecurity in Nigeria just weeks after President Goodluck Jonathan’s election late April for his first full term.

Police spokesman Yemi Ajayi on Friday said an investigation into the attack was under way.

“We will leave no stone unturned,” Ajayi told AFP. “We already suspected Boko Haram over the attack. So we are not surprised that they claimed responsibility for it.”

Several people were wounded in the explosion, according to Red Cross official Umar Abdul Mairiga, who said volunteers had picked up body parts, but could not say how many were killed.

Boko Haram, which means “Western education is sin,” launched an uprising in 2009 which was put down by a brutal military assault that left hundreds dead, mostly sect members.

It has pushed for the creation of an Islamic state and been blamed for shootings of police and community leaders, bomb blasts and raids on churches, police stations and a prison.

Boko Haram claimed responsibility for a spate of bombings near Abuja and in the north, claiming 18 lives, after Jonathan’s inauguration about two weeks ago.

But it was the first suicide bombing in Nigeria, although a would-be suicide bomber from Nigeria attempted to bring down an American airliner on Christmas Day in 2009.