BRENTWOOD -- Several people have been seriously injured in a multicar crash along Marsh Creek Road in Brentwood on Saturday, according to the California Highway Patrol.

The crash was reported around 3:37 p.m. just east of Deer Valley Road.

The CHP reported that at least two cars were overturned, and that several people had to be extricated by fire crews.

Three helicopters have been called in to fly patients to the hospital, and Marsh Creek Road has been closed in both directions while police and paramedics clear the area.

Drivers can expect delays and are asked to avoid the area.

Check back for updates.

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