Oregon State Police are looking for a man who assaulted another driver on the side of Interstate 5, then drove away in his truck Monday morning.

Troopers responded at around 7:50 a.m. to reports of a fight between two men on the southbound shoulder of the interstate near milepost 229, just before the Corvallis-Lebanon exit.

The suspect left before police arrived, driving away in a white Ford pickup truck towing a utility trailer. Police said an ambulance took the injured man to Good Samaritan Hospital in Corvallis. State Police Capt. Tim Fox said the man had “serious” head injuries, but did not know his status as of Monday evening.

Fox said the two men were traveling in separate vehicles, and that troopers believe the dispute happened because of “some kind of disagreement involving driving.” Fox said police are investigating whether either man had a weapon, and whether either man had been using alcohol or drugs at the time of the assault.

Fox said police have not yet identified the suspect and are asking any witnesses to the assault to contact the state police at 800-442-0776.

—Jayati Ramakrishnan; 503-221-4320; jramakrishnan@oregonian.com; @JRamakrishnanOR

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