A combined effort by Saint John Police and Fire is being credited with preventing a major fire overnight.

Police patrolling along City Road early this morning noticed a smell of smoke on the air. Officers did a search of the area and found a fire burning in a vacant building on Sewell Street.

Fire fighters were dispatched and quickly knocked the flames. Fire officials say it could have been much worse if the fire had burned much longer. They say the fire could have spread and caused extensive damage to homes on the street.