CAMPBELL (CBS SF) — Santa Clara County Fire units are at the scene of a four-alarm fire at a vacant commercial structure in Campbell Friday morning, according to authorities.

The fire is burning at a three-story building in the area of Dell Ave. and Knowles Dr. The Santa Clara County Fire Twitter account first posted about the fire at 10:17 a.m.

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Shortly before 10:30 a.m., fire officials called a second alarm. Residents are being asked to avoid the area.

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A fourth alarm was called at 11:30 a.m. A massive plume of smoke produced by the fire was visible from miles away.

Officials also noted SCCFD was is operating a drone overhead and that all private drones should be kept out of immediate area.

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Units beginning fire attack. PLEASE AVOID THE AREA. If I’m the area please use caution

Source: sanfrancisco.cbslocal.com.