A structure fire that got out of control near Pagosa Springs forced evacuations and prompted a disaster declaration from Gov. Jared Polis.

The blaze, called the Oak fire, had burned 150 acres as of Monday afternoon, according to incident officials. On Sunday, Polis declared a disaster emergency to support response efforts in Archuleta County in the southwestern part of the state. Polis also authorized the use of the National Guard to bolster firefighting efforts if necessary.

On Monday afternoon, FEMA authorized a federal Fire Management Assistance Grant to aid with firefighting costs.

The federal disaster agency approved the state’s request for the grant after determining that the Oak fire’s rapid spread, and proximity to 5,100 buildings and 2,000 homes, “threatened such destruction that it would constitute a major disaster,” according to a Monday news release. 

Katherine Fox, acting administrator for FEMA Region 8, said the Oak fire is the third Fire Management Assistance Grant approved for Colorado “in the last several days.”

The Oak fire is burning in the Elk Park/Ironwood subdivision west of Pagosa Springs and north of Colorado 160, officials said. The blaze quickly grew out of control, exceeding local firefighting capacity and leading the Archuleta County Sheriff’s Office to request state assistance.

A mandatory evacuation order has been issued for a one-mile radius around 38 Spruce Circle in Aspen Springs, incident officials said. Aspen Springs is approximately 10 miles west of downtown Pagosa Springs.

The declaration allows the state to mobilize its resources, including supplies, equipment and personnel, to assist in battling the fires and support the residents of the affected areas.

The state’s Division of Fire Prevention and Control is now the lead agency for the Oak fire, according to the governor’s office.

The fire is one of several burning around the state, highlighted by the Lee fire that’s burned well over 100,000 acres near Meeker.