Another Boko Haram bomber has hit a crowded market in Gombi town, Adamawa state, killing at least 20 persons.
The suicide bomber, said to be a boy, exploded the suicide vest, killing many bystanders
A vigilante leader put the death toll at 20 person, including the bomber .
Gombi was recaptured from Boko Haram in 2014 and since then, the insurgents have made several failed attempts to retake the town from the Nigerian military.