Colorado fire
A destroyed home is seen after the Soberanes Fire burned through the Palo Colorado area, north of Big Sur, California, July 31, 2016. Reuters/Michael Fiala

A wildfire in southwestern Colorado forced mandatory evacuations Wednesday evening, according to reports. The fire broke out in the afternoon, in the Lightner Creek area.

The La Plata County Sheriff’s Office said the fire was burning about three miles west of Durango in La Plata County, where about 140 homes have been evacuated, according to the Durango Herald. The fire has burned down at least one house so far, the Associated Press (AP) reported.

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Durango Fire Protection District official Scot Davis told the Herald the cause of the fire was yet to be ascertained. In the latest update, Durango Fire Protection District said Lightner Creek Road would remain closed through Wednesday night.

The fire was first reported reported shortly after 4 p.m. MDT (5 p.m. EDT) and by 7 p.m. MDT, it had spread to about 100 acres.

Evacuation orders were in place for all residents on County Road 207 north of the intersection of County Road 207/208, County Road 206 (excluding the Westwood Apartments, at the intersection of County Road 206 and Highway 160), Twin Buttes Subdivision, Animas High School and Hogs Back Trail System, according to the Herald.

The Lightner Creek Campground’s host Valerie Firth described the evacuations as “mass exodus,” the AP reported.

Evacuees were told to take shelter at the La Plata County Fairgrounds. Three heavy air tankers were reportedly ordered from Denver to help fight the fire.

Earlier in the day, the La Plata County Board of County Commissioners imposed Stage 1 restrictions on open burning south of U.S. Route 160 due to warm and dry forecast through this week, Durango Fire & Rescue said in a statement Wednesday.

“We have had good moisture through the winter and spring months that has led to dense ground fuels,” Butch Knowlton, La Plata County director of emergency management, said in the statement. “Those grasses and smaller fuels at the lower elevations have now dried and created conditions that allow for rapid fire development and movement.”

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In Stage 1 fire restrictions, smoking is limited to vehicles, buildings, recreational areas and 3-foot-wide areas cleared of vegetation. It also prohibits fireworks, use of explosive materials and any internal combustion engine unless fitted with an approved and functioning spark-arresting device, according to Durango Fire & Rescue. Furthermore, under the restrictions, welding and cutting operations are required to be carried within 20-foot radius safe zone that does not have vegetation and a fire extinguisher or pressurized water supply and proper hand tools and a fire watch worker are required.

“Flaring for production wells may be allowed with approval from the designated fire chief,” Durango Fire & Rescue’s statement read.

Violation of the fire restrictions is punishable and the person not following the rules would be fined up to $300 for each violation, according to Durango Fire & Rescue.