MAIDUGURI/KANO: A female suicide bomber killed 13 people at a crowded market and a military checkpoint outside the biggest city in northeast Nigeria, witnesses said on Friday.

A young female suicide bomber killed 13 worshippers when she blew herself up in a mosque in northeastern Nigeria, a witness and a vigilante aiding the military against Boko Haram said Friday.

“The bomber was a girl aged around 15 who was seen around the mosque when worshippers were preparing for the afternoon prayers,” vigilante Danlami Ajaokuta said of Thursday’s attack in Malari village, adding 12 had died and seven were injured.

“People asked her to leave because she had no business there and they were not comfortable with her in view of the spate of suicide attacks by female Boko Haram members.

“She made to leave but while the people were inside the mosque for the prayers she ran from a distance into the mosque and blew herself up,” he added, an account corroborated by resident Gajimi Mala.

There was no immediate claim of responsibility but Boko Haram has used both men and young women and girls as human bombs in the past, and Borno state where the attack took place has been the hardest hit by the insurgency.

The attack comes just a day after Boko Haram militants gunned down at least 145 people in three Borno villages, shooting Muslim worshippers during the holy month of Ramadan in the bloodiest day of attacks since new President Muhammadu Buhari came to power.

It is the fourth attack in a week in which at least 162 people have been killed, including four suicide bombers, as Boko Haram extremists appear to obey a Daesh order to step up attacks in the holy month of Ramadan. Nigeria’s homegrown extremist group became the Daesh group’s West Africa franchise earlier this year.

In the most deadly attack, the militants targeted several mosques in Kukawa town on Wednesday, gunning down nearly 100 praying worshippers. Kukawa is 180 km northeast of Maiduguri, the biggest city in the northeast.

The militants often defile mosques where clerics preach against their extremism. While they also have attacked churches, many more Muslims are among an estimated 13,000 people killed in the 6-year-old uprising.