SAN MATEO COUNTY (BCN) – A woman riding a bicycle was struck and killed by a big-rig near Portola Valley Thursday afternoon, a California Highway Patrol officer said.

The accident was reported at 3:39 p.m. on Alpine Road near the on-ramp to northbound Interstate Highway 280.

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Initial reports indicated the bicyclist had been hit by an 18-wheeler and was underneath the big-rig.   The victim was identified as 47-year-old Lauren Perdriau Ward.

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As of about 5:30 p.m., a small stretch of westbound Alpine Road remained closed, said CHP Officer Art Montiel.

The CHP is interviewing the big-rig’s driver, and is seeking witnesses to the accident. Anyone with information is encouraged to call (650) 369-6261 and ask to speak to Officer Keith Nielsen.

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