Oregon Public Broadcasting

Two off-duty Washington State Troopers and a dispatcher died in an early-morning house fire Monday near Zillah.  It's the single worst accident in the agency's history for officers either on or off duty. 

Yakima County Sheriff's detective Stu Graham says the house was "totally destroyed."

Stu Graham: "Some detection canines were used as part of the overall investigation.  There's a lot of things that are unknown about the fire and that's why we have assembled the investigative team that is here."

Graham says at this point there's no evidence the fire was intentionally set.

The Washington State Patrol identified the fire victims as Trooper Gary Miller and his wife Anne Miller-Hewitt.  She was a patrol dispatch supervisor. 

A newly minted trooper temporarily living with the Millers also perished in the fire. He's 30-year-old Kristopher Sperry.