WILLIAMS, CALIF. - A bus driver with a string of motor vehicle offenses and a history of substance abuse was arrested on suspicion of driving under the influence of drugs Monday after his casino-bound charter bus ran into a ditch, killing eight people.

Investigators also said the bus had an invalid license plate and they were looking into whether the driver had proper permits to operate the vehicle. The bus ran off the road Sunday while taking passengers to a Sacramento gambling hall. About 30 people were injured.

Records show 52-year-old Quintin Watts had been cited for speeding and other violations that resulted in loss of his license for nearly two years. He regained his driving privileges last January.

Watts was arrested as he lay critically injured in his hospital bed.

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