Fentanyl Made in the U.S.: How Clandestine Labs Operate Within the Country

“Sol Prendido” for Borderland Beat 

From the importation of chemical precursors to the procedures carried out in clandestine laboratories, fentanyl is also produced and distributed within the United States.

Two court records obtained by MILENIO reveal not only the long-standing existence of clandestine laboratories—where fentanyl is synthesized and pressed into pills—but also that the Drug Enforcement Administration (DEA) has chosen not to list them in its database of clandestine laboratories.

One such case occurred in Los Angeles, California, where a network of drug producers and traffickers was uncovered in late 2024 during an investigation that led to the discovery of three clandestine laboratories where fentanyl was being produced.

A woman, Suppatra Tansuvit, and two of her operatives—Eric Hanson and James Tinlsley—ran the operation, which was exposed when a Federal Bureau of Investigation (FBI) informant tipped off authorities about the presence of drug labs in the city, an area currently grappling intensely with the fentanyl overdose crisis.

Unlike many other cases, this one was investigated directly by an agent from the U.S. Postal Inspection Service (USPIS)—Lyndon Versoza—a specialist in money laundering and smuggling.

“They rent properties in the names of their identity theft victims, using them as short-term residences and as locations to mix and sell fentanyl, as well as to manufacture counterfeit identity documents,” Versoza noted regarding the case, according to court records.

**Raids on U.S. Laboratories**

In 2024, agents from the Los Angeles Police Department (LAPD) raided two of the network's fentanyl laboratories, where they discovered the materials and chemicals the criminal group used to manufacture the drug.

According to the CDC, as of 2023, California had by far the highest number of recorded fentanyl overdose deaths, with 7,203 cases, followed by New York, with 4,936. ...and Florida, with 4,593.

The first laboratory in Tansuvit’s network was raided on February 21, 2024, at 770 S. Grand Avenue in Los Angeles, specifically in Unit 7069 of the apartment complex.

Inside, authorities found seven kilograms of fentanyl, weapons, and fake identification documents, as well as laboratory equipment—such as metal presses and molds—and other drugs, including methamphetamine, heroin, MDMA, and psilocybin. There was also a kilogram of fentanyl that was being dried in a dehydrator machine.

The second laboratory was discovered after personnel from the Los Angeles Fire Department (LAFD) responded to a report of a fire at 2276 South Figueroa Avenue, a commercial rental building.

There, they found more than eight kilograms of fentanyl, along with equipment such as mixers, glass pipes, containers, mixing spoons, scales, chemical agents, presses, and a video surveillance system from which they obtained footage showing how the laboratory operated.

“The video continuously showed Tansuvit and Hanson mixing and selling drugs, sometimes while armed,” an investigator from the U.S. Postal Inspection Service stated in the case files. “In this video, I observed Tansuvit wearing latex gloves and a respirator mask. She was mixing powders—which appeared to be fentanyl and cutting agents—in mixing bowls and mixers.”

A third laboratory was brought to the attention of the Los Angeles Police Department by another informant; it was located at 8539 Lookout Mountain Avenue in Los Angeles. However, police were unable to reach the location before it was dismantled and the suspects fled. The site turned out to be an Airbnb rental.

Thanks to the video surveillance system in the second laboratory, authorities were able to confirm that it operated daily under the supervision of James Tinsley, who was also responsible for purchasing furniture and ventilation systems for the labs, as well as maintaining the financial ledgers.

The Tansuvit network, the postal inspector explains, was already on the radar of the Los Angeles police and the DEA itself. The 15 kilograms of fentanyl found in the first two laboratories are sufficient to cause fatal overdoses in at least 7.5 million people, according to estimates by the U.S. anti-narcotics brigade.

**Drop in Fentanyl Seizures at the U.S.-Mexico Border**

According to U.S. Customs and Border Protection, 2025 saw a decline in fentanyl seizures along the border with Mexico, dropping from 27,000 pounds in 2023 and 21,000 pounds in 2024 to 12,000 pounds in 2025, with the downward trend expected to continue into 2026.

Another case occurred in 2022 in Missoula, Montana—a riverside city near the U.S.-Canada border—where Andrew Kyle Whittecar, a U.S. citizen, was arrested while traveling to Wisconsin.

A highway patrol officer searched the vehicle in which Whittecar was traveling and discovered $3,000 in cash, cocaine, and more than 6,000 fentanyl pills, as well as a handgun and ammunition—findings subsequently confirmed by a laboratory analysis conducted by the DEA.

The second lab after a report.

The man stated that he was engaged in transporting fentanyl pills between various cities, prompting the initiation of an investigation against him. Security agents traveled to one of his properties in Stevensville, Ravalli County, where they located a clandestine fentanyl laboratory hidden within a storage unit.

There, they found pill presses, dyes, chemicals, and—according to U.S. prosecutors—"other substances indicative of the production of illicit pills." At that same location, they discovered 400 grams of fentanyl powder.

During a subsequent search, boxes containing laboratory equipment—such as glassware—were found, consistent with operations involving the mixing of chemicals for drug production.

"Two DEA forensic chemists examined the chemicals and equipment located in the storage units and concluded that they were sufficient to produce fentanyl," states the complaint filed against the man.

Furthermore, messages were found on his cell phones discussing the nature of laboratory production, such as "calculate production using the leftovers" or "make more drugs—between 80 and 100 grams per batch."

In its 2025 report on drug threats to the United States, the DEA acknowledged that fentanyl was becoming increasingly potent and dangerous—a result of experiments conducted by narcotics producers who were mixing the drug with other substances to increase its potency.

"DEA laboratories are reporting a downward trend in fentanyl purity. This should not be mistaken to mean that street-level fentanyl is any less dangerous," notes the anti-drug agency.

Moreover, the supply chains for the chemicals used in the manufacture of fentanyl are extensively documented. For example, on September 19, 2025, two executives from the Chinese pharmaceutical firm Amarvel Biotech—Qingzhou Wang and Yiyi Chen, both Chinese nationals—were sentenced on U.S. soil to 25 and 15 years in prison, respectively, for importing 200 kilograms of chemical precursors into the United States.

U.S. authorities, such as the DEA, identify Asian nations—specifically China and India—as the primary sources of supply for the production of fentanyl, a drug that is cheaper than cocaine and can be up to 50 times more potent than heroin.

Source: Milenio