DULUTH – Three wildfires fueled by hot and dry conditions and high winds about an hour north of Duluth remained out of control Monday, with at least three homes destroyed.

The Camp House fire near Brimson, Minn., was detected Sunday shortly after 1 p.m., prompting evacuations of dozens. Two other fires were also reported Monday.

On Monday, Gov. Tim Walz authorized the Minnesota National Guard to provide emergency assistance to help fight the Camp House fire.

One of the fires, more than 1,000 acres in size and growing, was discovered Monday afternoon just northwest of Brimson, according to Superior National Forest officials. It has destroyed at least one building. Called the Jenkins Creek fire, it's in a remote, forested area in the Superior National Forest, about 14 miles southeast of Hoyt Lakes, Minn.

The St. Louis County Sheriff's Office issued evacuation orders in areas near Indian Lake, Breda Lake and Cotton Township early Monday evening. The agency did not specify the size of the fire in a statement but said fire crews are battling flames.

The Minnesota Interagency Fire Center said Monday evening that the Camp House fire was about 1,250 acres. It was burning through large stands of spruce budworm-infested forest, the agency said. Such infestations also worsened the 2021 Greenwood fire near Isabella, Minn.

St. Louis County Sheriff Gordon Ramsay said Monday that shifting winds were making the blazes difficult to fight with hot spots reigniting.

The battle continues while nearly the entire state is under a red-flag warning for critical fire conditions. Temperatures in the 80s with gusty winds were expected in much of northeast Minnesota.

The wildfire operations supervisor for the Minnesota Department of Natural Resources said Friday the state brought in extra resources from out of state because of the "critical" fire danger.

Two helicopters that can lay down water, a dozen fire engines and a bulldozer have been brought in from other states to help if needed, William Glesener said. The tankers will anchor in Brainerd and Ely as part of preparation by the Minnesota Interagency Fire Center in Grand Rapids, which coordinates multiple state and federal agencies.

One heli-tanker, a CH-47 Chinook, can hold 2,300 gallons of water filled by a hose in 30 to 45 seconds, the sheriff's department said.

Glesener said the U.S. Forest Service likely had activated extra firefighting units just in case.

"The potential is there for large fire growth across the state," he added.

Minnesota's wildfire preparedness level was raised to 4 on a scale from 1 to 5 because of the extreme fire danger and current conditions, Glesener said.

The National Interagency Fire Center website states as preparedness levels rise, "so does the need for incident management teams."

Early Sunday afternoon, several fire departments were sent to the 2200 block of Hwy. 44 in Ault Township on a report of a wildfire spreading to the northeast. More than 50 houses and cabins were evacuated and at least three houses were destroyed by the Camp House fire, the St. Louis County Sheriff's Office said Monday.

Evacuation orders remain, and evacuation areas have been extended. The Forest Service said Cadotte Lake Campground was evacuated because of its proximity to the fires.

Brad Nelson owns a farm and properties on George Lake, and his family is among the evacuees of the Camp House fire. He was driving an all-terrain vehicle through his farm property Sunday afternoon when he spotted thick smoke billowing a few blocks away.

He reported the fire, he said, but "it had already gotten out of hand."

"They were perfect conditions: gusts of up to 35 miles per hour, low humidity. It couldn't have been worse," Nelson said.

One of the vulnerable properties is Camp House, for which the fire is named. The century-old camp is owned by Green Lake Lutheran Ministries, opened as a place for children of railroad workers in 1923. It sits on 120 acres on George Lake and runs popular youth and family programs.

"To see that space threatened by wildfire is heartbreaking, not just because of the land or buildings, but because of the sacred stories that live there," said Travis Aufderheide, executive director of the organization.

There are no known injuries.

The cause of the Camp House fire remains under investigation, but Nelson said it likely stemmed from a nearby property where someone was burning brush. Ramsay said the Jensen Creek fire was caused by a human, although how is still unknown.

There have been 475 reported wildfires since April 1, most of them human-caused. Fires have burned more than 10,000 acres. The five- to 10-year average is about 3,000 acres in April.

Bob Timmons and Elliot Hughes of the Minnesota Star Tribune contributed to this story.