The crash happened at Locust St. near Cole Avenue around 5:15 a.m.
The victims were taken to the hospital.
Walnut Creek police located the driver and was arrested.
Police said the names of the victims or the driver will not be released at this time.
This accident happened near the Walnut Creek Farmer's Market held on Locust St. which was closed for the day as the investigation continued.
It's unclear if the farmer's market was being set up when the accident occurred, but video did show tents set up.
Police are asking if anyone with information about this case to contact the Walnut Creek Police Department at 925-943-5844 or call the Anonymous Tip Line at 925-943-5865.
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