HERCULES (CBS13) – The search is on for the person who shot a five-year-old and her mother in an East Bay road rage incident. The girl is in the hospital with life-threatening injuries, police say.

Police say the drive-by shooting happened Saturday night on eastbound Interstate 80 near Willow Avenue in Hercules. Four people were in the car when someone shot into the vehicle, hitting the victims.

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The child was taken to the hospital with major injuries, while the mother sustained moderate injuries, according to a statement from the CHP Golden Gate Division. They say this was an isolated incident.

The freeway was shut down for four hours during the investigation.

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Officers urge anyone with information, or may have witnessed the incident, to call 1-800-TELL-CHP.