EL DORADO COUNTY, Calif. (KTXL) — Fire crews are battling the Caldor Fire in the El Dorado National Forest, which exploded in size overnight into Tuesday.

Grizzly Flats, Somerset and Happy Valley were ordered to evacuate late Monday and early Tuesday as the fast-moving flames moved through El Dorado County. 

More than 2,000 structures were threatened by the fire as of Tuesday morning, Cal Fire said.

Pioneer Elementary School, Mountain Creek Middle School and Walt Tyler Elementary School are closed due to evacuations, a school official told FOX40. The Pioneer School District and Union Mine High School will not be busing students on Grizzly Flat Road or in the community of Grizzly Flats.

As of Tuesday morning, the Caldor Fire has burned 6,500 acres and remains 0% contained, Cal Fire reported. Acreage was reduced due to better mapping.

Some homes in Leoni Meadows were lost to the fire, Cal Fire reported Tuesday morning, but crews were also able to save man homes in the area. 

Tuesday morning, at least one injury was reported by authorities. One person with “critical burns” was taken to the hospital by ambulance, officials said. The plan was for that person to be picked up by helicopter and taken to a local burn center. 

For online resources and the latest information on evacuation orders, click or tap here.

The U.S. Forest Service said the fire began Saturday evening four miles south of Grizzly Flats and 2 miles east of Omo Ranch.

Fire crews said the fire is burning in challenging terrain, making access difficult.

The El Dorado County Sheriff’s Office said Sunday communities in the area “should be on alert and prepared to evacuate.”

Residents can sign up for their county’s CodeRed emergency alert system for evacuation information using the links below.

The following locations have been listed as an evacuation centers: 

  • The Fireman’s Hall at 3734 China Garden Road in Diamond Springs, CA, in El Dorado County 
  • Cameron Park Community Center at 2502 Country Club Drive in Cameron Park, CA, in El Dorado County

Families who need assistance sheltering small animals can contact the El Dorado County Animal Services at 530-621-5795.

The cause of the fire is under investigation.

Click or tap here for additional information.