SUPERIOR, WI - An explosion with multiple injuries was reported at the Calumet Oil Refinery in Superior, WI Thursday morning.
According to the Superior Fire Department, there are at least 20 injured.
Smoke was seen billowing from the refinery just after 10 a.m.
Multiple crews were called in to assist in the response.
Neighbors on Facebook reported the explosion shook their homes.
Hospitals are preparing to treat victims of the explosion.