At least five people were killed by a suicide bomb in a car outside police headquarters in Maiduguri, Nigeria on Friday, according to the BBC.
The police said that following the blast security forces attacked a suspected Boko Haram hideout, prompting a fierce gun battle, reported the BBC.
The BBC was told by the police that one policeman and four civilians were killed.
The Borno state police commissioner, Bala Hassan, told Reuters that four people were killed, including one policeman and three civilians. The suicide bomber allegedly drove the car into the entrance of the police headquarters.
"He was driving a Toyota Camry, which he tried to drive right into the station. When he couldn't do this, he detonated the bomb," said Hassan.
Witnesses told Reuters they suspected the death toll could be higher.
No one claimed responsibility for the attack.
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The northeastern city has been the center of the Islamist group Boko Haram's insurgency, according to Agence France Presse. The insurgency has killed more than 1,000 people since mid-2009.
Boko Haram's mosque and headquarters were located in Maiduguri, until they were destroyed in 2009 in a military assault.
A special military task force has been stationed in the city, which has been hit by bombings and shootings in recent months.
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On Tuesday, Nigerian soldiers killed at least 16 militants near a Boko Haram hideout in Maiduguri, said AFP.
President Goodluck Jonathan's administration has said that talks with Boko Haram will be held "on the condition that their leader will come out and announce a cease-fire for three months or a minimum of 40 days," according to a Nigerian Muslim cleric, Sheikh Dahiru Usman, who said he was in touch with government officials and Boko Haram leaders, according to Bloomberg.
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