NEWARK -- Two North Jersey residents admitted their roles in a drug trafficking scheme that involved obtaining prescriptions for oxycodone and selling the narcotics for profit, prosecutors said Tuesday.

Rhonda Musallam, 41, of Fairview, pleaded guilty Tuesday in Newark federal court to an oxycodone distribution charge, Acting U.S. Attorney William E. Fitzpatrick announced in a statement.

Another member of the scheme, Robert O'Brien, 60, of Bloomfield, pleaded guilty Aug. 15, to conspiracy to distribute oxycodone, officials said.

Fifteen of the 16 people charged in the drug conspiracy have been convicted, according to the U.S. Attorney's Office. The 16th person died in April 2015.

Those involved in the scheme obtained prescriptions for oxycodone and other drugs from New Jersey doctors, filled them at pharmacies in Belleville and other areas to sell the narcotics for profit, officials said.

Musallam admitted she supplied others in the plot with oxycodone between June and July 2014, according to documents filed in the case. She confessed to selling 70 pills for $1,000.

For his part, O'Brien admitted that he received and paid for filled prescriptions for oxycodone pills on behalf of others in the drug scheme.

Agents with the Drug Enforcement Administration uncovered the drug trafficking operation in an investigation that involved confidential sources, surveillance and intercepted text messages and phone calls.

Noah Cohen may be reached at ncohen@njadvancemedia.com. Follow him on Twitter @noahyc. Find NJ.com on Facebook.

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