A Lynn man has pleaded guilty on drug trafficking charges in a scheme that uncovered what the U.S. Attorney’s office says it believes to be “one of the largest single-location seizures of fentanyl and methamphetamine in Massachusetts and the region.”

Sebastian “Bash” Bejin, 34, pleaded guilty in federal court in Boston to charges related to conspiracy, possession and intent of distributing controlled substances. Federal prosecutors say that nearly 220 pounds of drugs, primarily fentanyl and methamphetamine, were seized during the investigation.

The charges each carry a sentence of at least 10 years and up to life in prison, according to sentencing guidelines.

Bejin is one of three defendants charged in connection to the large-scale North Shore drug trafficking conspiracy. The cases against the other two, Emilio Garcia and Deiby Felix, are pending.

The investigation began with an overdose death in Salem in July 2023, according to the U.S. Attorney’s office. Investigators then put their sights on the three defendants.

On Nov. 1, 2023, investigators searched four locations in Lynn they say the defendants frequented.

“The searches resulted in what is believed to be one of the largest single-location seizures of fentanyl and methamphetamine in Massachusetts and the region,” the U.S. Attorney’s office wrote in a statement following Bejin’s plea.

At that location, investigators seized nine kilograms, or about 20 pounds, of “pink hear shaped fentanyl-laced pills pressed to look like candy,” federal prosecutors said. Further investigation led to the seizure of more than 75 kilos, or about 198 pounds, of fentanyl and methamphetamine, along with more kilos of cocaine and cutting agents.