WASHINGTON -- A November of 2017 Keystone Pipeline spill that leaked about 407,000 gallons of crude oil in over South Dakota farmland near the North Dakota border was likely caused by an expanding crack after the pipe was damaged during installation, the National Transportation Safety Board said in a report.

The report, issued Thursday, July 5, said a metal-tracked vehicle likely damaged the pipe and the fatigue crack grew until the rupture of the pipeline near Amherst, S.D., about 50 miles northeast of Aberdeen in the northeastern part of the state.

Keystone’s detection leak system detected the spill and Keystone’s Operational Control Center in Canada shut down the pipeline, but the crude oil still spilled.

There were no injuries associated with the incident.

A spokeswoman for pipeline owner TransCanada Corp.said this past April the pipeline spill was twice as big as originally reported when they estimated it at 210,000 gallons.

The new number made the spill the seventh-largest onshore oil or petroleum product spill since 2010, as reported to the U.S. Department of Transportation.

Repairs have since been made and the cleanup is done. TransCanada resumed using the pipeline 12 days after the leak.