A helicopter responding to the Derby fire ended up in an Eagle County lake on Friday afternoon, although fire officials said it’s not clear what happened. The pilot had only minor injuries.

The fast-growing wildfire is burning on 4,112 acres with no containment and has forced mandatory evacuations in northwest Eagle County.

The “aircraft incident” happened about 4:10 p.m. in a lake 13 miles west of the Eagle County Airport, White River National Forest administrator Curtis Keech said at a community meeting Friday night.

The pilot was picked up by another helicopter and taken back to the airport, where he was checked out for minor bumps and bruises and refused further medical treatment.

Fire officials notified the National Transportation Safety Board of the incident, and U.S. Forest Service crews are headed to the scene, Keech said.

Five wildfires burning on Colorado’s Western Slope — the Lee, Elk, Derby, Stoner Mesa and Crosho fires — have together burned more than 168,000 acres, or about 264 square miles.

The Derby fire was expected to push toward the popular Sweetwater Lake on Friday, while the Lee fire remains 3 acres away from becoming the fourth-largest wildfire in state history. The fire burning in Rio Blanco County between Meeker and Rifle grew 3 acres on Friday and has a footprint of 137,758 acres,.

The fires have threatened hundreds of homes, evacuated Colorado communities and prompted state, U.S. Forest Service and Bureau of Land Management land closures.

Derby fire, in Eagle County

The wildfire burning fire north of Sweetwater Lake is 0% contained and was expected to continue pushing south toward the lake Friday, according to a morning update from fire officials.

The Derby fire in the White River National Forest was burning on 4,112 acres as of Friday night. The fire, which was sparked by a lightning strike, started burning on a remote cliff face near the Flat Tops Wilderness about 13 miles northwest of Dotsero.

The fire prompted mandatory evacuations in Eagle County on Tuesday and tripled in size Wednesday to 2,624 acres.

At least one building has been destroyed by the wildfire, according to a Thursday morning briefing from Operations Section Chief Philip Knaub. It’s unclear what type of building it was. Firefighters were able to save other buildings.

The 211 personnel on site are focusing on the southeast side of the fire near Sweetwater Lake.

“Suppression efforts were mostly successful,” Knaub said Friday.

Fire officials anticipate the blaze to continue moving south. The weather looks somewhat favorable for suppression efforts, including possible rain, Knaub said.

The Colorado Department of Public Health and Environment issued an air-quality health advisory for the area because of smoke in western Eagle County and eastern Garfield County.

Lee and Elk fires, in Rio Blanco County

The Lee fire between Meeker and Rifle, which is burning 137,758 acres, hasn’t grown much in recent days and is at 80% containment.

The Lee fire is the fifth-largest wildfire in Colorado on record, according to the state’s Division of Fire Prevention and Control.

It’s also 3 acres from surpassing the Hayman fire, which consumed 137,760 acres in 2002.

The Lee fire started seeing containment jumps Saturday, after rainy weather helped firefighters gain full control of the nearby 14,518-acre Elk fire, which is now 100% contained.

The two drought-fueled wildfires together destroyed five homes and 14 outbuildings.

Stoner Mesa fire, west of Rico

A wildfire burning in the San Juan National Forest near Dolores grew only slightly Thursday night and Friday to 10,186 acres while containment grew to 32%, according to a Friday night update

Several nearby towns, including Rico, remain on pre-evacuation notice. The edge of Dolores County along County Road 38 to the West Dolores campground also was given pre-evacuation orders, according to the county’s emergency management team.

The west side of the fire was the most active Friday morning.

Crosho fire, near Yampa

The Crosho fire burned at 2,072 acres between Rio Blanco and Routt counties and was 57% contained as of Friday night.

Officials decreased the number of structures threatened by the fire to 22 from more than 200 in a Friday morning update.

Fire crews have contained the eastern perimeter of the fire, officials said.

Pre-evacuation orders remain in place for multiple areas around the fire, and county roads in those areas remain closed to non-residents. Mandatory evacuation orders were lifted Monday.