ANTIOCH (CBS SF) — Police got quite a surprise when they made a routine traffic stop this week in Antioch. Inside the vehicle was a pile of forged stolen checks, Social Security cards and mailbox access keys.

Antioch police said the driver, pulled over about 11:20 a.m. Monday at L and West 18th streets, was a parolee on post release community supervision, meaning the subject has agreed to allow warrantless law enforcement searches of vehicles, residences and property.

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A search of the vehicle turned up a number of stolen checks made out to the subject in amounts up to $10,000, police said, along with stolen identification and Social Security cards, and numerous mailbox access keys.

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The man, whose identity was not disclosed, was booked at County Jail in Martinez.