One man was killed and three other people were injured in a 4-vehicle crash on I-5 near Conway on Thursday afternoon.

Troopers say a car traveling in the southbound lanes crossed the median into northbound traffic near the Highway 534 interchange, hitting another car head-on. The driver who crossed the median was a 19-year-old woman in a Honda Civic.

A 64-year-old man was found dead at the scene. Two other people, a 23-year-old woman from Tukwila and a 42-year-old woman from Oak Harbor, were taken to Skagit Valley Hospital with minor injuries.

Troopers are investigating whether drugs played a role in the crash &#8212 being treated as a possible vehicular homicide &#8212 after finding a pipe in the 19-year-old woman’s car, according to The Seattle Times reports. The woman, who was also injured, told police she was distracted by her dog.

I-5 was closed in the northbound direction for a few hours while troopers investigated. Lanes reopened just before 6 p.m. Drivers were encouraged to take detours.