Two people, including a bomber¹, have died in an explosion at Nigeria's police headquarters in the capital, Abuja, the police say.

尼日利亚警方称，位于首都阿布贾的警察总局发生爆炸事故，包括一名人体炸弹在内共有两人死亡。

Police spokesman Olusola Amore said Islamist group Boko Haram was suspected of being behind the attack.

The blast in the car park of the police base destroyed many vehicles and a large plume² of smoke could be seen rising from the scene.

A Red Cross spokesman told the BBC that another four bodies had been recovered.

"Six to be precise. Six bodies from the explosion," Nigerian Red Cross official Taiye Olaniyi told the BBC's Focus on Africa programme, adding that many of them had been "very badly mutilated（残缺的，破坏的） ".

Seven other people were wounded in the explosion, five of whom were being treated in hospital, the Red Cross said.

The BBC's Jonah Fisher in Lagos says that, for the Nigerian authorities, the attack is an embarrassing strike at the very heart of their security establishment.

In the last few weeks, Boko Haram, which usually operates in the north-eastern city of Maiduguri, has been stepping up its attacks on security targets.

The group said it was behind a series of bombings in the capital that took place hours after President Goodluck Jonathan's inauguration³（就职典礼） last month.

On Tuesday, Nigeria's police chief promised to decisively deal with the group by sending more troops and equipment to the north, declaring they would be finished within a few months.