WATCH: Attorney General Garland holds news briefing on fighting fentanyl supply

The Justice Department has announced it has filed criminal charges against four Chinese chemical manufacturing companies and eight people over allegations they illegally trafficked precursor chemicals for fentanyl.

Watch the news briefing in the player above.

The indictments filed in two federal districts in New York mark the first time the U.S. has aimed to prosecute any Chinese companies responsible for making the precursor chemicals used to make the painkiller.

“As alleged in our filings, just one of these China based chemical companies shipped more than 200 kilograms of fentanyl related precursor chemicals to the U.S. for the purpose of making 50 kilograms of fentanyl, a quantity that could contain enough deadly doses of fentanyl to kill 25 million Americans,” Attorney General Merrick Garland said.

Garland told reporters two arrests have been made in the case that was filed in the Southern District of New York.

“What the defendants did not know at the time is that the purported traffickers they were dealing with were, in fact DEA confidential sources and the 200 kilograms of fentanyl related precursors they shipped to the U.S. were received by DEA agents.”

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Garland said three other Chinese-based chemical manufacturers faced charges in the Eastern District of New York.

“As alleged in the indictments, each of these companies also supplies precursor chemicals to the U.S. and Mexico, among other places, knowing they will be used to produce fentanyl or other controlled substances,” he said.

“In 2022, the DEA, together with our federal, state and local law enforcement partners, seized more than 50.6 million fentanyl-laced fake prescription pills,” he said. “That is more than double the amount seized in 2021.”