Four suicide bombers detonated their explosives on Wednesday evening in the northeastern Nigerian city of Maiduguri, leave 14 people dead and a further 29 wounded authorities said.

Nigerian police spokesman Victor Isukwu said the two male and two female bombers targeted crowded parts of Muna Gari suburb in the city of more than a million people.

Agence France-Presse cited Bello Dambatta, the chief security officer of Borno State's emergency response agency as saying that the first suicide bomber blew himself up close to where evening prayers were being held.

Another bomber then entered a house before setting off explosives, killing a pregnant woman and her child.

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The other two suicide bombers blew themselves up before reaching their targets, he added.

Boko Haram suspected

No one immediately claimed responsibility for the attack, which was immediately blamed on Boko Haram. The Islamist group has waged an almost decade-long insurgency in northeastern Nigeria, and carries out regular attacks in the Lake Chad region which sits on the joint borders of Cameroon, Niger, Chad and Nigeria.

Authorities said the use of multiple suicide bombers was a hallmark of similar Boko Haram attacks. The group often pressures women and children to carry out suicide strikes.

At least 20,000 people have been killed and more than 2.6 million people made homeless in northeast Nigeria since the group launched its insurgency.

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Despite the Nigerian government's insistence that the group had been "crushed" after it was beaten back from key territory it once held, vicious attacks on the military and civilians continue.

Maiduguri is the capital of Borno state and the city worst hit by the jihadist insurgency. Since June alone, at least 221 people have been killed in bombings and gun attacks in northeast Nigeria, according to a tally by the Reuters news agency.

mm/kl (AFP, AP, Reuters)