Frenchtown fire crews rushed to the scene of a grass fire in Alberton early Thursday morning, but the cause of how the fire started is still unknown.

Frenchtown Rural Fire Department officials said the fire was located behind the Indian Bible School by Penny Creek, and was spotted by a driver on the road.

"Once our crews responded they saw about 15 to 20 feet flame lengths," spokesman Mel Hotz said. "It was burning in some grass and also some brush as well as dried brush. They were able to wet line around it pretty quickly and contain the fire and right now we’re working on chainsaw work."

Hotz said fire crews were working to cut down burnt trees in the area today since the 2 a.m. blaze.

Officials reminded Montanans yesterday that all controlled burns should remain under absolute supervision after fire danger changed to high this week in Missoula County. Open burning was banned for Ravalli County yesterday due to extreme fire danger.

The cause of the fire is still under investigation.