ARLINGTON — Arlington Police are investigating the cause of a head-on collision that occurred June 26, sent two people to the hospital and closed Highway 9 for more than three hours.

The accident occurred at approximately 4:20 p.m. in the 19300 block of Highway 9, and was so violent that both vehicles plunged down an embankment adjacent to the highway. Due to the injuries involved and the location of the vehicles, Highway 9 was closed between the 204th Street NE intersection and the Eaglefield Drive and Crown Ridge Boulevard intersection for at least three hours.

The driver of one vehicle, a 30-year-old male resident of Bellingham, was transported to Cascade Valley Hospital with minor injuries. The driver of the second vehicle, a 38-year-old male resident of Arlington, was taken to Arlington Municipal Airport for transport to Harborview Medical Center by Airlift Northwest Helicopter.

The cause of the crash is still under investigation.