A San Diego area drug trafficker tied to what investigators say was one of the region’s most potent powdered fentanyl seizures is headed to federal prison for more than eight years, closing the book on a cross-border case that stretched from Tijuana to Madrid.
Yesterday, U.S. District Judge James Simmons sentenced 36-year-old Aaron Leib Kobisher, who prosecutors say went by the alias “El Kobi,” to 8 years and 1 month in federal custody, or 97 months, after finding him responsible for trafficking methamphetamine, fentanyl, and cocaine between Tijuana and U.S. distribution networks. Prosecutors told the court the sentence capped a multiyear probe that produced seizures and arrests on both sides of the border, according to the San Diego Union-Tribune.
Kobisher had pleaded guilty in 2025 to a conspiracy charge covering the three drugs and agreed not to fight extradition after his arrest in Spain, the San Diego Union-Tribune reported. Friday’s sentencing in San Diego federal court marked the latest chapter in a case that blended old-school cartel violence with the grim mathematics of modern fentanyl trafficking.
DEA Lab Flagged a ‘Staggering’ Fentanyl Shipment
Federal agents tied Kobisher to a June 2021 seizure of roughly two kilograms of powdered fentanyl, more than four pounds, that quickly got the attention of chemists at the DEA Southwest Laboratory. In testing, that load turned out to be the most concentrated fentanyl sample the lab had ever seen, according to a press release from the U.S. Attorney’s Office. The finding was not just a chilling data point, it also helped investigators map out shipments and build a broader conspiracy case against Kobisher and five co-defendants, the Justice Department said…