GARY, Ind. (AP) — The federal Bureau of Alcohol, Tobacco, Firearms and Explosives will help the Gary police and fire departments investigate a series of recent suspicious fires. Gary Fire Chief Sean O’Donnell said Tuesday that firefighters from throughout Lake and Porter counties worked Saturday night and early Sunday to extinguish blazes at 17 vacant buildings in 11 different locations throughout the city. He says some of the structures were fully engulfed when firefighters arrived. No injuries were reported among residents or firefighters. Gary Mayor Jerome Prince says a rash of seven fires on April 21 was also considered suspicious and will be investigated as well.