A wildfire estimated to be 6 acres in size is burning in Jefferson County, according to West Metro Fire Rescue.

The fire, dubbed the West Ranch Fire, is burning in the foothills west of Ken Caryl Valley. The West Metro Fire Rescue announced the fire on Twitter shortly after 3 p.m. Sunday. 

Fire officials said they do not know what started the fire. The fire is fully uncontained as of 6 p.m.

Multiple crews have responded, and are looking for "the best access to the fire," according to West Metro Fire. Over 30 firefighters and 20 apparatus worked the fire Sunday.

The Inter-Canyon Fire Protection District said the fire was spreading through brush in the early evening, pushed by erratic winds of 10 to 15 mph. However, cooler temperatures and sleet moving into the area just before 6 p.m. helped slow the fire's progress.

Rocky conditions, steep terrain and darkness hindered firefighters' efforts in the evening, the fire protection district said. Crews will monitor the blaze overnight and continue containment on Monday.

No structures are currently threatened, though the fire is close to some structures in the West Ranch community. If evacuations were necessary, the Jefferson County Sheriff’s Office would notify residents. 

Firefighters reach 50% containment on wildfire burning west of Denver

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