The Lee Fire has forced the evacuations of two counties, including homes and a Colorado prison, as one of the largest wildfires in the state's history continued to grow, and officials warned residents in remote areas to be ready to leave.

Evacuation orders were already issued for mountain communities over the weekend as the Lee Fire burned more than 167 square miles in Garfield and Rio Blanco counties, with only 6% containment. No injuries or structural damage have been reported.

Faced with the threat, the 179 people incarcerated there were removed from the Rifle Correctional Facility on Saturday "out of an abundance of caution," according to the Colorado Department of Corrections. They were temporarily relocated about 150 miles (240 kilometers) away to the Buena Vista Correctional Complex, the department said.

The Lee Fire, burning through trees and brush about 250 miles west of Denver, is now the sixth-largest blaze in state history, according to the Colorado Division of Fire Prevention and Control.

More than 1,000 firefighters are battling the blaze, working to keep the flames west of Colorado 13 and north of County Road 5, officials said.

Health officials issued air quality advisories related to smoke from the Lee Fire and the 23-square-mile (60-square-kilometer) Elk Fire that burns just to the east.

The six largest wildfires in Colorado history, including the Lee Fire, each burned more than 100,000 acres during their lifetime, with the Cameron Peak Fire (2020) being the only fire to burn more than 200,000 acres, according to the Colorado Division of Fire Prevention and Control.