BRENTWOOD, CA : Brentwood police investigate fatal Hwy. 4 crash on Tuesday, 3rd September 2019

Investigators are looking into a fatal midday vehicle crash that blocked a lane on a Highway 4 on-ramp, authorities said Thursday.

Just after noon, California Highway Patrol officers responded to eastbound Hwy. 4 lanes at the westbound Balfour Road on-ramp for reports of a collision involving a red Mercedes two-door sedan and a semi-truck.

When officers arrived, they found both vehicles on the right side of the on-ramp. Brentwood police also responded, and learned that the semi-truck had been eastbound on Balfour. As the truck turned left to enter the on-ramp, it struck the Mercedes.

The driver of the Mercedes, a 70-year-old woman, was taken by medical helicopter to John Muir Medical Center in Walnut Creek, where she was pronounced dead. Her identity was not immediately available Thursday night.

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