PORTLAND, Ore. (KOIN) — Three people were killed in a crash on Interstate 5 a few miles south of Castle Rock on Saturday afternoon, Washington State Patrol reported.

Anna-Christie Ireland, 43, was driving northbound when she struck the back of a car parked on the side of the freeway. The impact caused the parked car to hit a tow truck in front of it, killing the tow truck driver who was standing between the vehicles. Officials said the tow truck had its emergency lights fully activated at the time.

The driver and a passenger inside the parked car were killed. Another passenger — a 25-year-old man — was injured.

Troopers identified the tow truck driver as 63-year-old Arthur Anderson of Longview. The driver was 55-year-old Richard Stoker and the passenger was 54-year-old Karen Stoker, both of Battle Ground. They died at the scene.

Investigators said they believe Ireland may have been driving under the influence. She was booked into the Cowlitz County Jail on three counts of vehicular manslaughter and one count of vehicular assault.