I doubt it's happened during the past 10 years, but back in the early 60's a family friend named William Brashers owned a farm in the Ball Hills area of Thurston County as an investment. He rented out the farm to a family who raised some beef and replacement heifers. The area is just north of the Vail Tree Farm. One winter (late 60's) the renter had a livestock kill and called the game department to complain about the "wolfs" that took down a heifer. He was assured there was no such critter in Washington State, and should it occur again feel free to protect his property and shoot the coyote or coydog doing the damage.
I don't remember who shot it, but I do remember being told that a game warder looked over a dead timber wolf in the back of a pickup truck at the Wolf's Market parking lot. The story as I (grad school age) remember it was that the wolf was identified as an eastern timber wolf. It had to have been imported. I recall no effort being made by the game department to protect them then as they were considered a non native species, and addressed as any destructive dog would have been; if it's attacking livestock stock, shoot it. A lot of fingers pointed to Weyerhaeuser as a way to drop deer browsing damage in the Vail unit while being able to keep closed gates.
I admit it's all hearsay since I never saw a wolf myself. Anyone else old enough on this thread to remember this story?