A brush fire on a hillside behind a Wenatchee neighborhood is threatening eight homes.

Fire officials told residents to be ready to evacuate as the wildfire spread to several ridge lines behind the community on Sunday morning.

The Wenatchee World reports the fire reported at 2:15 a.m. came within 20 feet of one house on Skyline Drive.

Fire spokeswoman Kay McKellar says the cause of the fire is under investigation. About 100 firefighters are on the scene. A helicopter is also dropping water on the fire.