SAN FRANCISCO (CBS SF) — Federal prosecutors and local law enforcement have charged 18 people with trafficking fentanyl and other narcotics in San Francisco’s Tenderloin District, fueling the gun violence in the area and accidental drug overdose deaths, authorities announced Tuesday.

Among those charged are eight people who face federal charges of participating in two separate drug trafficking conspiracies based in the Tenderloin. The U.S. Attorney’s Office for the Northern District of California said in a press release the two organizations are alleged to have supplied the Tenderloin with “copious amounts of narcotics, including several varieties of fentanyl.”

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According to both federal complaints, the investigation of the two drug rings took over a year and involved the U.S. Drug Enforcement Administration (DEA), the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) and the San Francisco Police Department. The charges were filed on October 14 and unsealed on Tuesday.

The first complaint alleged two brothers – Luis Ochoa, 24, of Alameda, and Roger Arteaga, 28, of Berkeley – headed a drug trafficking organization that primarily distributed large quantities of fentanyl, using a branding scheme to sell the fentanyl in different colors.

Since at least May, Ochoa, Arteaga, and three co-conspirators supplied fentanyl for resale to multiple local narcotics re-distributors, according to the complaint.  Some of the co-conspirators also allegedly engaged in street-level drug sales.

A single drug seizure by law enforcement resulted in the recovery of approximately one kilogram of fentanyl, a quantity with the potential to create 500,000 lethal doses of the drug. At the time of Ochoa’s arrest, among the evidence seized was four pounds of fentanyl, or 1.8 kilograms.

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The second complaint alleges Fernando Viera, 27, of Oakland led a drug-distribution organization, describing him as a mid-level drug trafficker who allegedly supplied drugs to multiple resellers and street-level dealers in the Bay Area.  Those street-level dealers, in turn, sold the drugs in the Tenderloin.  Aside from fentanyl, the dealers also sold methamphetamine, heroin, cocaine, and cocaine base.

“The disturbing upward trend of organized fentanyl sales in our cities is a triple threat: fentanyl is deadly, its organized trade attracts violent offenders, and its sales and use devastates neighborhoods,” said Acting U.S. Attorney Stephanie Hinds in a press statement.  “Our prosecutions target those who seek to turn our city streets into open fentanyl marketplaces.”

“The staggering loss of life we’ve seen due to drug overdoses is a public health calamity San Franciscans haven’t witnessed since the height of the AIDS crisis,” said San Francisco Police Chief Bill Scott in a statement. “Our street drug trade has been nearly twice as deadly as COVID-19 in San Francisco. While the primary chemical culprit is fentanyl, drug-related gun violence is beginning to take an increasingly troubling toll.”

San Francisco police said approximately 12.5 pounds — or 5.7 kilograms — of fentanyl was seized in the joint operation. With
an estimated minimum lethal dose of just 2 milligrams, the operational haul of fentanyl theoretically represents enough to fatally overdose 2.85 million people.

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The operation also seized approximately 1.5 pounds of methamphetamine; 1.5 pounds of cocaine base; approximately 1.25 pounds of heroin, 22.8 grams of oxycodone, nearly $27,000 in U.S. currency, three firearms, and two 30-round high-capacity magazines.