BISMARCK, N.D. (AP) — Two more people have been indicted in what authorities say was an international synthetic-drug ring that led to overdose deaths in three states.

The indictments of Ronnie Helms, 30, of Acworth, Georgia, and Braden Foley, 28, of Olympia, Washington, are part of an investigation into the international trafficking of powdered fentanyl and other synthetic drugs.

A dozen people have been charged in the case, which is called "Operation Denial," which prosecutors say is a reference to both the efforts of law enforcement to deny drugs and the apathy of citizens toward the problem.

Helms and Foley face drug distribution and conspiracy charges and are being brought to North Dakota, U.S. Attorney Christopher Myers said. Court documents do not list attorneys for the two men. Neil Fulton, head of the federal public defender's office for the Dakotas, said early Friday that his office had not yet been made aware of the indictments.

The investigation into the trafficking ring began with the overdose death in January of Bailey Henke, 18, of Grand Forks. There have been a total of 12 victims, four of whom died and eight who suffered serious injury due to overdoses, Myers said. Court documents indicate the victims were in North Dakota, North Carolina and Oregon.

"Co-conspirators arranged to obtain controlled substances from outside the United States, including, but not limited to, Canada and China," the indictment against Helms and Foley said. "These controlled substances were then distributed across the United States."

Myers said in a statement that the "national and international" investigation is ongoing and includes U.S. Homeland Security, local and state authorities in both North Dakota and Oregon, and the Royal Canadian Mounted Police. Authorities allege that the drug ring involves a Colombian man who trafficked the drugs while serving a prison stint in Canada.

Another person charged in the case is Brandon Hubbard, 40, of Portland, Oregon, who allegedly told authorities he could be the largest fentanyl dealer in the United States. He has pleaded not guilty to five charges, including conspiracy to distribute controlled substances resulting in death.

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