Authorities are investigating the cause of an explosion at a private hog farm northwest of Bruce, in east central South Dakota.

Brookings County Sheriff Martin Stanwick says no people or hogs were hurt in the incident about 9:15 p.m. Wednesday. But he says
there was extensive damage to walls and water lines inside the
building, and parts of the roof were blown off.

Stanwick says the blast happened in a central office area, away from where hogs were kept. He did not immediately know how many hogs were in the area at the time.

Stanwick says no foul play is suspected. He says a state fire marshal was called to the scene Thursday to investigate the cause.

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