Inside a high-security Chinese factory pumping out fentanyl

YICHANG, China — Behind a large glass wall, a worker in full protective gear watches as hundreds of tiny glass bottles whizz by every minute, sterilized, filled and packaged by a ballet of robotic arms

YICHANG, China — Behind a large glass wall, a worker in full protective gear watches as hundreds of tiny glass bottles whizz by every minute, sterilized, filled and packaged by a ballet of robotic arms.

Inside each ampule is the substance at the heart of the geopolitical strife between the United States and China: fentanyl, the deadly opioid at the center of a deal outlined by Presidents Donald Trump and Xi Jinping on Thursday.

NBC News got exclusive access to the headquarters of Yichang Humanwell Pharmaceutical, the largest producer of the drug in China, and indeed Asia, at its sprawling complex in the central city of Yichang.

Humanwell says that it only supplies fentanyl for use in hospitals and that it does not export any medication to the United States, Mexico or Canada. In 51 years of operating, “we have never had a single incident of a drug going missing — not a single dose has ever been lost,” its president, Du Wentao, said in an interview inside his factory, which is surrounded by high fences wrapped in concertina wire and electric sensors.

Humanwell is one of only five companies in China licensed to produce fentanyl for use in hospitals, and it makes around 100 million doses of fentanyl variants each year.