AKIPRESS.COM - Three female suicide bombers have carried out an attack that has killed at least 27 people in north-eastern Nigeria, BBCreported citing officials.

Dozens were injured when the women blew themselves up outside a refugee camp near Maiduguri in Borno state - a stronghold of the Islamist militant group Boko Haram.

There has been an upsurge in violence in the city in recent months.

Boko Haram has been fighting to set up an Islamic state since 2009.

A report published by US anti-terrorist researchers last week said it is the first insurgency in history to use more women suicide bombers than men.