AUBURN, Wash. - One person was struck by an oncoming vehicle after walking onto Highway 18 late Tuesday night.

Washington State Patrol is investigating the collision and wants to know why the person was on the roadway in the first place. At this point in the investigation, there are no visible signs that may provide any clues.

Initial calls to police describe the person attempting to flag down traffic near the right-hand lane.

The oncoming vehicle did not have time to react or avoid the pedestrian, according to WSP. They do not believe the driver was impaired at the time of the incident.

All lanes of Westbound Highway 18 were reopened around 3:30 a.m.