GLENWOOD SPRINGS, Colo. (AP) — A wildfire southeast of Glenwood Springs was 10 percent contained Wednesday morning.

The Red Canyon Fire has scorched about 350 acres. The Post Independent reports that the fire is threatening 20 structures, though none is in immediate danger. No injuries have been reported.

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Officials believe the fire was sparked Monday by lightning, though they’re still investigating.

Also Wednesday, forest officials in southern Colorado upgraded containment on the West Fork Complex to 80 percent.

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The West Fork Complex has charred more than 171 square miles in the Rio Grande National Forest. Forest spokesman Mike Blakeman says the West Fork Complex isn’t being actively fought, but threatens no structures. He predicted the wildfire wouldn’t be fully out until snow falls, though he said the burn area will reopen by hunting season Aug. 31.

Investigators still haven’t pinpointed the cause of June’s Black Forest Fire, which killed two people, destroying 488 homes and charring 22 square miles.

El Paso County sheriff’s Lt. Jeff Kramer said it appears the fire was human-caused. He said investigators are still awaiting reports on some laboratory tests.

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