ZIMMERMAN, Minn. (WCCO) — Department of Natural Resources firefighters are standing by for what is shaping up to be another dangerous wildfire weekend.

Only now they’ve got a new concern — unmanned aircraft, otherwise known as drones.

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Firefighting planes and a helicopter rest on the tarmac of the Princeton airport. Their crews are on high alert for a grass fire that would press them into action.

“It was a concern right away,” firefighter Mike Peltier said.

Peltier has been a longtime DNR firefighter based at Zimmerman, near the Sand Dunes State Forest. He was riding aboard a DNR helicopter recently when it was called to a large grass fire in Otsego.

The firefight was also captured on video by the operator of a drone. The problem is, Peltier and the pilots flying water drops over that fire didn’t know the drone was also in the air.

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“Afterwards we found out there was a drone on the fire and we didn’t see it, we were not even looking for it,” Peltier said.

That’s why the DNR is now asking drone operators to stay at least five miles from an active wildfire. The DNR’s wildfire aviation supervisor, Bill Schuster, says pilots and crew members are busy enough watching for fire movement, people and power lines to worry about spotting something so small and unexpected as a drone.

“The consequences would not be good,” Peltier said.

Firefighters say they don’t want any other close encounters while on the fire line. They say the job is tough enough without having to worry about an aerial disaster.

The DNR’s Schuster says he’ll be meeting with the state fire marshal and legislative leaders to, hopefully, put some teeth into their request.

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Current policy requires that pilots disengage and pull away from the fire fight whenever a drone is spotted in the area. Removing the aerial attack from a fire is not good, but it’s simply too dangerous to keep flying when aerial tanker pilots can’t see what’s up in the sky.