(PUEBLO COUNTY, Colo.) — Multiple agencies are responding to a one-acre fire burning north of Pueblo, and the Pueblo County Sheriff’s Office (PCSO) is warning drivers that smoke may be visible from I-25.

PCSO tweeted about the fire just before rush hour on Tuesday afternoon, July 18. PCSO said the Sheriff’s Office Emergency Services Fire team and the State Division of Fire Prevention and Control were working a one-acre fire along Fountain Creek. The fire was reported at about 12:30 p.m. on Tuesday.

A helicopter is assisting with firefighting efforts, as PCSO said the fire is burning in an area that is difficult to access by foot or by vehicle due to terrain.

PCSO said the fire is burning in dead trees and brush along Fountain Creek. The fire is 75% contained and no structures have been threatened.

PCSO said crews expect to have the fire fully contained within a few hours. The cause of the fire is still under investigation.