A structure fire just off the Gunflint Trail a few miles south of the U.S.-Canada border killed a trail maintenance worker and his dog, northern Minnesota officials said.

Cook County officials said they were alerted shortly before 11 p.m. Wednesday to the blaze on Poplar Creek Drive south of the Gunflint Trail and within the Boundary Waters Canoe Area Wilderness.

The Gunflint Trail Volunteer Fire Department arrived to the scene deep in the woods within about 30 minutes and found multiple structures on fire, the Sheriff's Office said. Crews cleared the scene about 2:40 a.m. Thursday after all open flames were extinguished.

Curry R. Thompson, 50, and his dog, Ginny, died in the fire, according to the Sheriff's Office.

"It is absolutely devastating to lose a life to fire, and our sympathy is with the family of Curry Thompson," Sheriff Pat Eliasen said in a statement.

The cause of the fire was not immediately determined.

Thompson headed maintenance and grooming for the nearby Banadad Ski Trail System, said Andy Jenks, who heads a nonprofit dedicated to the 25½-mile system's upkeep.

Jenks said on the Banadad Trail Association's Facebook page that Thompson and his dog "went to sleep, and an explosive fire broke out, and both buildings burned to the ground."

Jenks said he spoke to Thompson not long before the fire erupted and "he was very happy with our current situation and was looking forward to ... work on the trail."