Updated

Four Boy Scouts who went missing during a canoe trip along the Wisconsin-Illinois border were found unharmed before dawn Sunday after a helicopter pilot spotted their campfire, authorities said.

The Rock County sheriff's office in Wisconsin reported that the four boys were last seen around 1:30 p.m. Saturday while canoeing with the rest of their troop and a scout leader on the Sugar River in Wisconsin.

The 12- and 13-year-old boys, who were from Illinois, launched their canoes from a campground in Avon, but became separated from their group at a portage near Sugar River Park. After portaging, the main group continued on. When the four boys didn't catch up, the scout leader went back upstream to look for them, but couldn't find them in the winding river system.

The scout leader assumed the missing boys had somehow got in front of the group, so the leader rejoined the group and they paddled on to their destination at the Winnebago County Forest Preserve in Illinois.

They realized the boys weren't there, and the Winnebago County sheriff's office was called about 7 p.m. Saturday, triggering a search by multiple agencies in both states that included johnboats, ATVs and a helicopter.

At about 1 a.m., the crew of a helicopter from the Illinois Department of Transportation located a campfire in the woods along the river, a couple miles north of the Wisconsin-Illinois border.

The pilot landed the helicopter and found the boys, who were flown to the Shirland Fire Department in Illinois and reunited with their families. None of the boys was injured.

Officials said the boys apparently took a wrong bend in the river and got lost. When it got dark, they got out of the water, started a campfire and waited for help.

Rock County sheriff's officials said the scout leader had taken the boys' cellphones so they wouldn't get lost in the river. If the boys had had them, officials said, they would have been able to call for help or emergency officials would have been able to trace the phones' signals.

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