For years, U.S. officials have complained that Chinese laboratories are a major source of illicit fentanyl, the potent opioid that has driven a stunning increase in overdose deaths on this side of the Pacific.

On Wednesday, Chinese and American law enforcement officers stood side-by-side at the U.S. Custom House in New Orleans to announce what they billed as a first-of-its-kind joint investigation into fentanyl production.

The operation began with a suspect in New Orleans and ended at a laboratory in the Chinese province of Jiangsu.

Officials said that between November and January, Chinese investigators arrested 21 people and halted the export of more than 20 million doses of fentanyl.

“This is the first case of its kind, with China and the United States working together to identify a transnational crime organization. It’s a good news story,” said Shawn Harwood, a Department of Homeland Security Investigations attaché in China.

Observers said the investigation, which has yet to result in any federal prosecutions in the U.S., could herald a new era of cooperation between law enforcement agencies in the two countries. Yet they cautioned that it could also be the last of its kind if a trade dispute, sparked by President Donald Trump’s tariffs on Chinese goods, escalates.

The operation occurred as the U.S. grapples with a crisis of drug overdose deaths. More than 72,000 Americans died of drug overdoses in 2017, a 9.5 percent increase from the year before. Nearly 30,000 of those deaths involved synthetic opioids like fentanyl, the Centers for Disease Control and Prevention said.

A congressional commission said last year that fentanyl often begins its journey to the U.S. in Chinese labs. Although China has banned fentanyl production in response to U.S. pressure, Chinese chemists have been engaged with a cat-and-mouse game with their own government by creating variations of the drug that are subsequently banned.

Chinese officials, who deny that their country is a major source of fentanyl, announced Wednesday that they will ban 32 new substances starting on Sept. 1, including two fentanyl variants.

Officials were vague on the recent investigation’s origins in New Orleans. But they said agents with Homeland Security Investigations, a division of U.S. Immigrations and Customs Enforcement, identified a suspect in New Orleans connected to fentanyl trafficking in August 2017.

Information from that investigation led agents to China, the presumed source of the fentanyl. U.S. officials said they referred the case to their Chinese counterparts.

The Chinese National Narcotics Control Committee and Narcotics Control Bureau created a special task force of 100 officers to investigate, officials said. Ultimately, they dismantled a lab and recovered the equivalent of millions of potentially fatal doses of fentanyl or fentanyl precursors.

Despite the lab’s immense output, its size was closer to a small methamphetamine operation than a large pharmaceutical lab, said Thomas M. Annello, the HSI deputy special agent in charge in New Orleans.

The investigation in China has now circled back to the United States. Officials said they are working to connect suspects to 35 U.S. addresses where distributors mailed or attempted to mail illicit drugs.

U.S. officials declined to disclose the fate of the initial suspect from New Orleans, who was not a Chinese citizen.

“I would say they’re in custody, but I can’t give you any information beyond that. I can tell you they’re not free and roaming the neighborhood,” said Bryan Cox, the southern region communications director for ICE.

The U.S. officials said they still hope to initiate prosecutions here. Their Chinese counterparts were in New Orleans this week with the aim of further developing the case.

Even if the case results in no more arrests, it could still have important diplomatic implications. Notably, the operation in China began the same month that Trump complained about a “flood of cheap and deadly” fentanyl that was “manufactured in China.”

Trump also promised to bring up the issue during his state visit with Chinese President Xi Jinping in Beijing that month.

Markos Kounalakis, a visiting fellow at the Hoover Institution, said he suspects that pressure from Trump played a role in Chinese authorities “rare” cooperation on this case.

“It seems to square with the timing from that last year,” he said. “I would say that it is recognizing one of the president’s priorities, something he brought up with President Xi personally.”

However, Kounalakis warned that cooperation could fall victim to larger issues like the tariff dispute or national security tensions. He noted that, for unclear reasons, China has recently withheld samples of a dangerous avian flu virus, despite an international health agreement.

Kounalakis added that Chinese officials have repeatedly stated that the real drug problem begins with demand in the U.S.

Chinese officials promised more cooperation in the future as they spoke Wednesday in the Custom House’s ornate Marble Hall.

“The success of this case has demonstrated a commitment to crack down on fentanyl crimes by law enforcement officials in both countries,” said Chen Shaoujun, who helped lead the operation as a vice mayor in the Chinese city of Xingtai.

Speaking through an interpreter, Chen added, “I believe that with close law enforcement cooperation between the United States and China, we will make great new achievements fighting narcotics crimes.”


Follow Matt Sledge on Twitter, @mgsledge.