The malfunction of a motor home's exhaust system is being blamed for igniting about 10 small brush fires along U.S. Highway 97 south of Bend, Oregon.
The Central Oregon Interagency Dispatch Center says firefighters from several agencies worked quickly to contain and mop up the fires late Tuesday afternoon and evening.
Deputy Fire Marshal Dan Derlacki says the largest reportedly burned about five acres.
Law enforcement officers scrambled to temporarily divert traffic.
KTVZ-TV reports that several motorists pulled over not just to report the fires but to grab shovels and tackle the blazes themselves.
Deschutes County sheriff's Sgt. Aaron Harding says the motor home was located a short distance away and the driver cooperated with the investigation.