Arraignment took place this week in downtown Los Angeles for one of five people—including two active-duty U.S. Marines—accused in a drug-dealing conspiracy that involved the sale of oxycodone pills laced with fentanyl that led to the fatal overdose of another Marine.

Jordan Nicholas McCormick, 26, of Palmdale, is alleged to be the supplier of LSD, ecstasy, cocaine and fentanyl-laced oxycodone pills to co-conspirators, according to the U.S. Attorney’s Office. McCormick pleaded not guilty.

Lance Cpls. Anthony Ruben Whisenant, 20, and Ryan Douglas White, 22, who are stationed at Camp Pendleton, were arrested Sept. 22 on a federal grand jury indictment charging one of the Marines and three civilians with conspiring to distribute narcotics to civilians and members of the Marine Corps, one of whom suffered a fatal drug overdose in May.

Whisenant allegedly distributed drugs to fellow Marines, including the one who died, and White is charged with being an accessory after the fact for allegedly attempting to hinder the apprehension of Whisenant and an alleged drug supplier named in the indictment.

The 14-count updated indictment also charges Gustavo Jaciel Solis, 24, of Sylmar, who allegedly sold McCormick’s drugs to civilians and military personnel, and Jessica Sarah Perez, 23, of Pacoima, who allegedly distributed narcotics, including fentanyl and cocaine, to civilian customers.

On Aug. 11, Solis and Perez were indicted on fentanyl and cocaine distribution charges, and Solis was indicted on firearms-related charges. They have pleaded not guilty and their trial date is scheduled for Oct. 27. Solis is in federal custody and Perez is free on $25,000 bond.

The updated indictment adds McCormick—who is also in federal custody—Whisenant and White as defendants, in addition to adding charges to the original indictment. Prosecutors contend the conspiracy lasted from last November through September and involved multiple sales of fentanyl-laced oxycodone to an undercover buyer, often for amounts exceeding $1,000 per buy.

On May 22, Solis sold 10 pills of oxycodone laced with fentanyl to an active-duty Marine who died of a drug overdose in the early morning hours of May 23, the indictment alleges.

In addition to the conspiracy charge, McCormick, Solis, Whisenant and Perez face substantive charges of distribution of narcotics, including fentanyl. McCormick and Solis are also charged with possessing firearms in furtherance of drug crimes.

If convicted, McCormick and Solis would face a sentence of 10 years to life in federal prison, and Whisenant and Perez would each face up to 20  years behind bars. White, if convicted, would face up to 10 years in federal prison.