MARTINSBURG, W.Va. (AP) — More than three dozen people have been indicted on charges stemming from a multistate heroin trafficking operation.

The 163-count indictment was unsealed on Tuesday in U.S. District Court in Martinsburg.

U.S. Attorney William J. Ihlenfeld II says the operation was extensive. Heroin was distributed in West Virginia, Maryland, Virginia and Pennsylvania.

The indictment charges that 27-year-old Brian Alexander Hall of Maryland orchestrated the operation. Forty other defendants from West Virginia, Pennsylvania and Maryland are accused of obtaining heroin from Hall in Baltimore and the surrounding region and then redistributing the drug.

Ihlenfeld says in a news release that the investigation was conducted by federal and local law enforcement from multiple jurisdictions.

Thirty-five defendants, including Hall, have been arrested. Two were already in state custody and two others haven’t been located.

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