ACTON (CBS) — Crews have contained approximately 30 percent of a brush fire that has scorched at least 40 acres in Acton, authorities reported.

The blaze broke out shortly before 4 p.m. Tuesday in the 4700 block of West Crown Valley Road, according to county fire inspector Tony Imbrenda.

The fire initially moved quickly through heavy brush and destroyed several structures. Blowing embers started several spot fires in the area.

By 7 p.m. the blaze was moving at a dramatically slower rate, according to L.A. County Fire.

(credit: CBS)

A voluntary evacuation was called shortly after 7 p.m. and residents were told they could go to High Desert Middle School, located at 3620 Antelope Woods Drive.

Southbound Soledad Canyon Road has been closed at Crown Valley Road and the northbound side has been closed at the Santa Clara River, the California Highway Patrol reported.

The blaze has also forced the closure of Metrolink tracks north of the Via Princess station. Metrolink is working to provide buses to carry passengers to the Acton, Palmdale and Lancaster stations.

Los Angeles County firefighters are using helicopters to help fight the brush fire. The U.S. Forest Service was also preparing to join the effort.

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