TWISP, Wash. (AP) — Authorities have issued immediate evacuation notices for about 40 homes being threatened by a wildfire in northcentral Washington.

The Crescent Mountain Fire is burning in subalpine fir, grass and meadows near the headwaters of the Twisp River west of Twisp. It was started by lightning on July 29.

The fire had been holding a little less than 2 miles (3.2 kilometers) from the closest home, but authorities say it became more active on Friday, prompting the evacuation notices. Campgrounds in the area had already been closed.

Residents were urged to head toward Twisp. The Red Cross planned to set up a shelter at the Methow Valley Community Center.