Here's how B.C. crews are using controlled burns to fight wildfires

With B.C.'s Keremeos Creek wildfire continuing to threaten homes and communities, wildfire crews are using controlled burns to contain the blaze.

The fire, discovered on July 29 southwest of Penticton, measured at just over 6,800 hectares Tuesday morning. In recent days, specialists have conducted planned ignitions to secure the perimeter of the fire.

Over the weekend, for example, crews were in the Olalla area, near ongoing evacuation orders. Mike Morrow, ignition specialist for the BC Wildfire Service, said the area has "very tough ground."

"In preparation for the ignitions, the crews began by digging handguard all the way along, stringing a hose fully charged with water," he said in a video posted online by the wildfire service.

"Once they had water they did a test burn to see what the actual burning conditions were."

Morrow said conditions were favourable so they continued down the line of the mountain right above Olalla to eliminate the natural fuel in those areas.

"Doing the ignitions in this steep, inaccessible ground, tying it off and cleaning up the area, it allows that area to be contained, mopped up and secured quicker, which allows residents back into their homes sooner," Morrow explained.

In its morning update Tuesday, BCWS confirmed more planned ignitions were conducted on Monday, with more to come.

"Helicopters and an ignition specialist will be on site again today. Hand ignitions will continue to bring the fire down to safe, workable ground for crews and are crucial for creating reliable containment. During operations, increased fire activity and smoke may be visible from Olalla, Keremeos and Penticton," BCWS said in its update.

"These ignitions are expected to be low-intensity and will serve to secure control lines. Helicopters will be standing by in all planned ignition areas to support operations, with structural crews monitoring any properties that may be adjacent to these operations."

More than 400 firefighters are assigned to the Keremeos Creek blaze. Hundreds of properties are under evacuation order and evacuation alert.