A massive storm that tore through the heart of Minnesota's lake country forced some of the state's most popular resorts and campgrounds to shut down Monday at the height of vacation season.

Downed trees crashed into cabins, crushed campers, blocked roads and knocked out power lines.

Winds that hit 70 miles per hour blew into the area Sunday night along a swath that was 8 miles long and 3 miles wide from Gull Lake to Lake Hubert, forcing hundreds of campers and resort guests to evacuate and the owners of Madden's On Gull Lake and Cragun's Resort to shut down for cleanup.

Cragun's, which was left without power on Monday, evacuated 600 guests and expects to reopen in about a week. Madden's on Gull Lake, which evacuated 300 guests to a storm shelter on Sunday, is likely to remain closed for two weeks.

"Our golf courses and the resort took a hit," said Kathy Reichenbach, Madden's marketing director. The storm, which damaged some resort buildings and felled many trees, was one of the worst that Reichenbach has seen in the 34 years she's worked at the resort.

About 8,000 properties lost power Sunday night. And by Monday, 6,000 customers were still without power.

The biggest obstacle is removing all of the large trees that have fallen and broken an estimated 100 power poles, which all need to be removed and replaced, according to Minnesota Power, which recruited workers from the Twin Cities to help with the storm cleanup. The number of broken power poles could grow as they continue to assess the damage. But the power company expects to have power restored in the area by Thursday.

Mark Ronnei, Grand View Lodge resort general manager, said damage to the resort could total up to six figures. The golf course there is expected to reopen Tuesday, but "our beach was turned upside down," he said. About 200 trees on the resort were destroyed.

Campers at Gull Lake Dam and Recreation Site near Brainerd were evacuated, and the camp is closed indefinitely, according to the U.S. Army Corps of Engineers.

Hundreds of trees are down in and around the campground, the corps said. The camp's boat ramp also is closed.

One to 2 inches of rain fell in the area, but it was the high winds that did most of the damage, according to the National Weather Service in Duluth. There was no tornado, but the storm's straight-line winds reached weak tornado levels, said Carol Christenson, Duluth NWS warning coordination meteorologist.

"This was one of the bigger storms that I've seen, especially in the area, in recent memory," she said. "We generally get this type of storm one or two times a year."

By morning's light, power lines were down and hundreds of trees were uprooted, snapped or left tilting. Parts of roofs were blown off, roads were blocked and buildings and vehicles were crushed.

A large section of metal bleachers at Brainerd International Raceway was twisted like a pretzel.

Nine miles north of Brainerd, a camp facility on North Long Lake lost electricity after about 100 large trees and several power poles were knocked down, according to the State Patrol and the camp's operators. One of the felled trees landed on a training building.

Parents headed to Legionville to retrieve the 135 kids at the safety patrol camp for middle-schoolers that's run by the American Legion, said State Patrol Sgt. Neil Dickenson.

North of Brainerd along Round Lake, Ray Bonestroo began calculating the damage to a cabin that's been in the family since the 1920s and to his car that appeared to be totaled.

"We lost at least 10 old trees and some of our dock sections," said Bonestroo, 53, who lives in Plymouth. Another tree gouged the roof on the three-season porch of the cabin, which was built in 1928 by Bonestroo's great-grandfather.

Bonestroo's immediate concern now is getting a tarp over the damage to prevent any rain from adding to the pain.

The rest of the week's forecast calls for highs in the lower 80s, with storms falling into the maybe-maybe not category starting Wednesday.

Star Tribune staff writers Mary Lynn Smith, Tim Harlow and the Associated Press contributed to this report. Paul Walsh • 612-673-4482