Law enforcement officers have stepped up patrols around an oil pipeline site in Minnehaha County after vandalism was discovered.

Sheriff's Capt. Jason Gearman says vandals broke through a chain link fence recently that surrounds an above-ground section of the Dakota Access pipeline near Highway 19, north of Humboldt. A valve inspector has since repaired a hole, but Gearman says it's still a safety issue because any tampering can cause extreme situations, such as an explosion.

Gearman says they have notified the FBI. The sheriff's department is encouraging any citizen that sees something suspicious to report it.

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