LOS ANGELES (CBSLA) — A Lynwood man was found guilty Wednesday of organizing and leading more than a dozen armed robberies of small pharmacies across Southern California for prescription painkillers like oxycodone.

After a two-day bench trial in April, U.S. District Judge John A. Kronstandt issued his ruling Wednesday, finding 26-year-old Tyrome “Boobie” Lewis of eight felony charges, including conspiracy to interfere with commerce by robbery, conspiracy to distribute oxycodone, interference with commerce by robbery, possession with intent to distribute oxycodone and knowingly using and brandishing a firearm during a violent crime.

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Federal prosecutors say Lewis conspired with a crew between May 2018 and July 2019 to pick independent “mom-and-pop” pharmacies to steal oxycodone and similar prescription medication. During the trial, prosecutors presented evidence that Lewis assigned roles to the crew members and served as lookout during the robberies. The Lewis-led crew struck pharmacies in Glendale, Bellflower, Paramount, Cerritos, Hawthorne, South Los Angeles, Pico Rivera, Huntington Park, Claremont, Westminster, Fullerton, Anaheim, and Riverside, and came to be known as the “Oxy Bandits.”

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Investigators determined the 15 robberies across Southern California shared similar characteristics – small pharmacies robbed for prescription drugs that were stuffed into trash bags or trash cans, while employees were threatened or intimidated with a black semi-automatic handgun to open the medication vault.

Federal prosecutors say Lewis is just one of 21 people charged in a larger, joint FBI and Los Angeles County sheriff’s investigation into a series of armed pharmacy robberies since 2019.

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Lewis, who faces a statutory maximum sentence of life in federal prison, is scheduled to be sentenced on Sept. 23.