CIMARRON, N.M. (AP) - Firefighters spent Thursday building containment lines around a wildfire that has charred more than 300 acres in Cimarron Canyon.

The Horseshoe fire was spotted Wednesday afternoon and quickly grew because of high winds. Cimarron Canyon State Park is temporarily closed to visitors because of the fire.

Authorities say no homes or buildings are threatened and the fire is several miles away from the nearest structures in the Ute Park community.

Authorities believe the fire was started by a power line.

After running into snowpack, the flames moved east at a slower pace while crews built containment lines. The blaze was 30 percent contained by Thursday afternoon despite wind gusts of up to 50 mph.

About 180 firefighters and eight engines are battling the fire.

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