Firefighters responded Friday to a grass fire in Sauget outside the American Bottoms Treatment Plant.
Investigators say the fire started when a transformer exploded, causing a 13,800 volt power line to fall on grass along American Bottoms Road, according to KSDK.
The area is south of the Poplar Street Bridge along Illinois Route 3.
Fire officials said they got reports of smoke in the administrative building. They said the downed power lines likely melted phone lines into the building and caused the smoke.
There is no widespread power outage and no one was hurt.