Someone set several fires in wildlife areas of grass and trees Sunday in Polk County, two that each burned 120 acres or more, said Polk County Sheriff's Sgt. Jim Tadman.
About 35 firefighters from volunteer departments in Erskine, Mentor and McIntosh responded, including Tadman, who also serves as a firefighter in Erskine, Minn.
"It started about 1:10 a.m., Sunday, on the south side of Union Lake," said Tadman, who found several spots where someone had started fires. Over the next few hours, two other calls came in of fires to the north and east, also in grasslands and woods, he said.
No buildings or other structures burned, but it was clear someone deliberately set the fires across a radius of eight to 10 miles, driving or walking north to south, roughly, he said.
"It was windy enough to keep it going, with all that dry stuff," he said.
Winds gusted up to 35 mph in the region later Sunday; by evening, rain fell across the area.
The state fire marshal will investigate. No suspects have been identified or questioned yet, Tadman said.
Anyone with information about them should call the sheriff's office in Crookston at (218) 281-0431.