Firefighters are working to contain a 50-acre wildfire that started burning southeast of Kenosha Pass Sunday afternoon.

They say the blaze, which does not appear to be threatening any structures, was caused by humans. How exactly people started the fire was not released.

Firefighters say the fire was first reported near County Road 56 just before 2:40 p.m. Sunday. There is no containment, and the fire is burning in grass, aspen, mixed conifer and ponderosa pine.

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Additional resources, including Americorps and a small hand crew, will report to the fire line Monday morning.

The fire has not prompted any closures, but the public is asked to be cautious on Lost Park Road, Forest Road 133 and on the Colorado Trail near Johnson Gulch.