String of structure fires baffle officials in Gary, Ind.

GARY, Ind. (WLS) -- A string of structure fires in Gary, Ind. has authorities baffled Saturday night.

One Gary official describes them as "multiple and almost simultaneous."

Fire engulfed a house in the 3600-block of Colfax around 1:30 Saturday morning. Then more calls came in.

Fire departments in Merrilllville and Lake Ridge assisted in dousing those flames.