NATIONAL CITY, Calif. (FOX 5/KUSI) -- A man was fatally struck by a vehicle early Wednesday morning while riding a bicycle in the South Bay, California Highway Patrol said.

The unidentified man was riding a bicycle around 1 a.m. on southbound Interstate 5, south of Mile of Cars in National City when he was struck by a BMW X3, authorities said.

The man was pronounced dead at the scene. Meanwhile, the driver of the BMW stayed and cooperated with the investigation, according to CHP.

Authorities stated that alcohol and/or drugs do not appear to be factors in the crash. The cause and circumstances surrounding the incident are being investigated by the CHP San Diego Area.

A toxicology report and the identity of the decedent will be released by the San Diego County Medical Examiner's Office.

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