Story highlights The fire at Glacier National Park has doubled in size to 4,000 acres

Part of the park's popular Going-to-the-Sun Road is shut down to allow for firefighting

(CNN) The fire in Glacier National Park in Montana has doubled in size to 4,000 acres and forced new evacuations, according to park officials.

"The fire is moving quickly in dry, heavy timber with extreme spread potential," the park service said in a press release. "Due to windy conditions and extreme fire behavior, today's suppression actions were limited to aerial water drops and some on-the-ground crew work."

The Reynolds Creek Wildland Fire, which started Tuesday afternoon near Grizzly Point on the east side of the park, was located Wednesday about 10 miles from the St. Mary Visitor Center along the Going-to-the-Sun Road, and moving in a northwest direction.

Several backpackers in the vicinity of the fire were located and escorted to safety. Park rangers and firefighting personnel will keep searching for backcountry hikers in the area.

A photo posted by Cheyenne (@cheystirling) on Jul 21, 2015 at 9:45pm PDT

A photo posted by Megan Baumann (@megnbaumann) on Jul 21, 2015 at 4:51pm PDT

On Wednesday, the park service said evacuations have been ordered on the west side of St. Mary Lake and evacuations on the east side are expected.

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