Spokeswoman Kimberly Reason says the cause of the fire is under investigation but it could have been caused by frozen brakes that overheated.
The driver noticed a problem, pulled over and safely evacuated about 70 passengers, including a woman in a wheelchair.
Reason says there’s no official estimate of the loss, but the bus costs nearly $700,000 new.
Flames gutted the diesel-powered articulated bus and it burned for more than half an hour as Seattle firefighters poured on water and foam.
The Transportation Department says the fire at North 85th Street backed up morning rush hour traffic for 10 miles.
More Northwest Headlines
911 calls from fatal Twisp fire: ‘Send somebody fast’ Chemical fire in WWU chemistry building caused by spill Arrest made in downtown Seattle tourist attack Lawsuit: Western State Hospital staff ignored man choking Inslee heads out on 9-day trade mission to Korea and Japan The rest of the West is still burning Scientists, tribe study shrinking Washington state glaciers Foster Farms in Kelso fined for untreated chicken wastewater release
Our new comment system is not supported in IE 7. Please upgrade your browser here.