HELENA, Mont. — Montana National Guard officials say 15 troops and a Chinook helicopter are being sent to fight a fire burning the in the Beaverhead-Deerlodge National Forest.

Major Chris Lende says in a statement that the troops and equipment are departing Monday afternoon after being mobilized a day earlier.

They are assigned to the Meyers Fire burning 25 miles southwest of Philipsburg. The fire has burned 20 square miles (51 square kilometers) and was 4 percent contained as of Monday morning.

Last month, Gov. Steve Bullock declared a fire emergency in the state. The declaration authorized the National Guard to support wildfire response.

Lende says in his statement that the Montana Department of Natural Resources and Conservation requested the Guard’s assistance with the Meyers Fire.