A cow is suspected of causing a spill of natural gas liquids near a tributary of the Little Missouri River, North Dakota officials said.
The state Department of Health said a cow may have rubbed against a tank valve Tuesday, spilling about 20 barrels of natural gas condensate near Sully Creek, in western North Dakota, Fox News reported.
The site is owned by a subsidiary of Oneok Inc. based in Tulsa, Oklahoma.
Regulators said say cleanup is under way and booms are in place in Sully Creek as a precaution.