SEATTLE (CBS13/AP) — Eleven people have been indicted by a federal grand jury in a drug-trafficking conspiracy involving the sale of meth, heroin and cocaine, according to federal prosecutors.

“This drug trafficking group continued to bring large loads of drugs up to Western Washington even after law enforcement seized nearly 50 pounds of methamphetamine from one carload,” U.S. Attorney Brian Moran said Wednesday in a press release.

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“This investigation uncovered threats of violence and retaliation which made it critical that law enforcement move now on this drug ring.”

According to the indictment, the 11 people smuggled the drugs into the U.S. from Mexico and brought them up the West Coast to sell in Pierce, King and Snohomish counties.

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Two of the men are from California and the rest from Washington state, Moran said.

Since the investigation began, law enforcement has seized large amounts of drugs including a 49-pound load of methamphetamine that was coming to Washington state from California.

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On Wednesday, officials seized 18 pounds of heroin, 25 pounds of methamphetamine, as many as 15,000 fentanyl pills, more than $150,000 in cash drug proceeds, and 23 firearms, Moran said.