A spill of oil and saltwater at a well site in Mountrail County on Tuesday has been contained on-site, according to regulators.

The North Dakota Department of Mineral Resources, Oil and Gas Division stated in a release Wednesday that a spill had been reported on a site seven miles south of Ross.

The release stated that the spill occurred at an oil well site operated by Norway-based Statoil.

Statoil reported that 427 barrels of oil and 142 barrels of saltwater are believed to have spilled onto the site. The company believes the spill was caused by a valve failure at the site.

According to the department, an inspector was sent to the site following notification of the incident.