The fire was sparked at the end of a runaway lane at the base of Anarchist Mountain, off Highway 3, and an Osoyoos RCMP officer witnessed the accident unfold.
Detachment area commander Sgt. Kevin Schur happened to be on the steep descent into Osoyoos at around 3:30 p.m. PT, driving behind a semi truck that appeared to be losing its brakes.
"I could smell the brakes and saw them heat up. I noticed that he wasn’t slowing very much," Schur said in a written statement.
"I slowed back, signalling traffic behind me to stay back, as I called in for fire and ambulance to be dispatched," he said.
The truck, which was hauling lumber, continued to gain speed, until the driver saw an out.
"Once he got near the bottom of the hill, he saw the runaway lane and took it, which is the safe and proper action to take,"
The truck sped off the road at the base of the mountain, and overturned in the runaway lane. The driver, who wasn't seriously hurt, got himself out of the cab.
"I was very relieved when I saw him climb out," Schur said.
Minutes later, the truck caught fire, and became fully-engulfed in flames. The fire spread to the dry brush at the side of the road and started ripping up the hillside, creating giant plumes of smoke.
Jeff Davies, a former CBC News reporter, was driving on the highway when he saw smoke in the sky, and pulled over to get a better look.
"I could see a huge smudge of white and grey smoke on the horizon, reaching up hundreds of metres into the sky," he said.
"It appeared to be [from] right at the base of a mountain, at the end of that runaway lane."
A spokesperson with the wildfire management branch estimated the fire was spread over an area between five and seven hectares in size as of 5 p.m. PT. Four fire crews and a water tanker are attacking the fire.
"I overheard talk of injuries but know nothing more," said Davies. "It is not blocking traffic but many people have pulled over to watch."
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