American Canyon Police said they found a man slumped over the steering wheel, the engine running, when they checked out a vehicle at 9:20 p.m. Wednesday at Via Firenze and Via Bellagio.
The motorist, Lavelle Dwayne Phillips, 32, of Vallejo was awakened and remained in a daze, police said.
Inside the vehicle, police said they found a loaded .45 caliber Glock semi-automatic pistol with an illegal 20-round magazine on the floorboard. Police said they also discovered suspected heroin packaged for sale, cash and marijuana.
Phillips was booked into the Napa County jail for possible charges of possession of a controlled substance while armed, possession of a concealed gun, possession of a firearm by an ex-felon or addict, driving under the influence of drugs and unlawful possession of a large- capacity magazine.
Phillips was still in custody Thursday afternoon, with bail set at $100,000.
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