PORTLAND, Ore. (KOIN) — According to fire officials, a fire at a Washington County home spread to one more and injured three people on Monday morning.

Around 10:20 a.m., Tualatin Valley Fire & Rescue responded to the report in the 11900 Southwest Lynnridge Avenue neighborhood in Cedar Hills. 

Once they arrived on the scene, TVF&R said its fire crews saw a single-story home “heavily involved with flames” that spread through the roof and front door. The blaze was then updated to a two-alarm fire to allow firefighters to request additional help.

Officials said the fire spread to a second house, which prompted crews to extinguish the flames and look for occupants in both homes. Other firefighters worked outside to stop the blaze from spreading to trees and brush, and to tend to a downed power line.

Additionally, TVF&R reported that two people exited the first home before fire crews arrived and were treated on the scene. American Medical Response then transported them to a nearby hospital with serious injuries.

The firefighters also shared that an occupant in the second residence exited safely before being treated on the scene.

Multiple agencies assisted with the fire. As of 3:41 p.m. on Monday afternoon, Tualatin Valley officials said an investigator was on the scene to determine the cause of the backyard blaze.