Ten people were killed in twin suicide bombings in Potiskum, northeast Nigeria, a police source and a civilian vigilante assisting the military against Boko Haram told AFP.
Eight vigilantes were killed in the first blast in the Igwanda area of the city at about 12:15 (11:15 GMT) while two died in the second outside a tavern and brothel in the Dorawa area.
There was no immediate claim of responsibility but Potiskum, the commercial capital of Yobe state, has been hit repeatedly by Boko Haram in its six-year insurgency, including by suicide bombers.
The first attack targeted the civilian vigilante office in the Igwanda area of the city and came after a man seen carrying laptops and other computer accessories was detained.
“We suspected he was a thief and then when he couldn’t explain how he came about the things that were found on him, we took him to our office for interrogation,” said one vigilante group member.
“But we didn’t know he had explosives on him. He detonated the explosives and we lost eight men, including our commander,” said the vigilante, who asked not to be named for his own safety.
A police source in Potiskum confirmed the attack.
“We took eight dead bodies of the vigilante men to the hospital and the remains of the suicide bomber.”
The second blast happened moments later in the Dorawa area of Potiskum at an open air tavern and brothel that has previously been hit by the Islamists.
The same police source said a man suspected to be a bomber was chased by an angry mob and set off his explosives before he was caught.
“Two people have been confirmed dead,” he added.
Boko Haram are keen to prove they are not a spent force despite a four-nation military offensive that has run them out of captured towns and villages since February this year.
The use of improvised explosive devices (IEDs) and suicide bombings has increased since May 29, when President Muhammadu Buhari took office vowing to crush the militants.
At least 162 people have been killed in some 17 separate attacks in that period, according to AFP reporting.