MOUNT CARMEL, Ill. (AP) – The operator of an Illinois oil pipeline is reporting 1,150 barrels of diesel fuel has spilled, resulting in the pollution of at least one river.

Marathon Pipe Line LLC says the equivalent of about 48,300 gallons of fuel has leaked from a pipeline near Mount Carmel in southern Illinois. In a statement, the company says it hasn’t determined the source of the leak, but has shut down its Two Rivers pipeline system as a precaution.

The Mount Carmel Register reports the Wabash County Sheriff’s Department has confirmed the leaked diesel has reached the Wabash River.

Telephone calls Monday to Marathon Pipe Line and the sheriff’s department for comment on the spill weren’t immediately returned.