EXCLUSIVE

Jimmy Bain, ex-bassist for the heavy metal band Dio, was busted for DUI and illegally possessing prescription meds after a car accident last night ... TMZ has learned.

According to police in Burbank, CA, Bain got into a minor accident -- in his '95 Toyota Camry -- around 9:30PM ... and responding officers suspected he was under the influence of something other than alcohol.

Cops say Bain failed a field sobriety test, and they also found Vicodin pills that were not prescribed to him.

Bain was arrested and booked for misdemeanor DUI and felony possession of prescription medication.

Cops say Bain, a founding member of Dio, also had an outstanding drug warrant. He was released on $60,000 bail.