Speaking after assuming office, Mr Umar said the appointment was his seventh posting to Borno.
Mr Umar explained that the two repentant Boko Haram members were arrested for theft.
About five fire fighting trucks were deployed to the scene to contain the situation.
Some of the affected structures consumed by the fire included essential commodities shops, boutiques, poultry and second hand materials shops, among others.
He said the terrorists fired several gunshots targeting voters from the top of Mandara Mountains, adding that five persons sustained injuries in the attack.
The gang of serial ritualists known specialise in dismembering body parts of their victims.
Commissioner of Police, Abdu Umar, said that seven cases were being prosecuted in court.
The report indicated that violence erupted on November 30 over the alleged encroachment of farmlands and murder of a farmer by unidentified assailants in the area.
The peace accord is designed to facilitate peaceful conduct of the 2023 elections devoid of thuggery, hate speech, fake news and violence.
The victim, a chief imam of his area, had returned from the mosque when the suspect, who was the second wife, allegedly mixed poison in his food.
