CLEARLAKE (CBS SF) — Cal Fire was using their ‘heli-torch’ to light backfires in terrain so rugged it couldn’t be reached by foot to keep the Rocky Fire from burning a roadway as the blaze burned in three Northern Bay Area counties.

The heli-torch is used to remove fuel from the area surrounding a fire to help prevent its spread.  A propane torch is suspended underneath the helicopter, and firefighters can pinpoint where they want to burn the vegetation.

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By Monday, the Rocky Fire had grown to consume 60,000 acres, with just 12-percent containment.

The heli-torch can be seen in action in a YouTube video below.

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