Federal agents arrested three suspects Tuesday in the Aug. 9 death of a correctional officer due to fentanyl exposure at the U.S. Penitentiary in  Atwater.

The arrests were announced in a news release by  U.S. Attorney Phillip A. Talbert.

The suspects are Jamar Jones, 35, an inmate at USP Atwater; Stephanie Ferreira, 35, of Evansville, Indiana; and Jermen Rudd III, 37, of Wentzville, Missouri.

According to court documents, they conspired to introduce narcotics into USP Atwater for Jones to sell. As part of that scheme, Jones and Ferreira had Rudd mail a letter laced with the narcotic to Jones that was fraudulently labeled as legal mail, prosecutors allege.

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Prison Mailroom Supervisor Died Aug. 9

Marc Fischer, a mailroom supervisor at the penitentiary, died on Aug. 9 after he reported feeling ill minutes after opening the letter. After evaluation by medical staff, he was taken to a hospital where he passed away, federal authorities said.

Another correctional officer also felt ill after coming into contact with the narcotics-laced letter but recovered.

The FBI, the U.S. Postal Inspection Service, and the Federal Bureau of Prisons, with assistance from the Drug Enforcement Administration, are investigating this case.

Assistant U.S. Attorney Robert Veneman-Hughes is the prosecutor.

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Arraignment Schedule

Ferreira is set to be arraigned on the complaint in the Southern District of Indiana, while Rudd will be arraigned on the complaint in the Eastern District of Missouri. Jones will appear next week in court in Fresno for his initial appearance.

The defendants face prison sentences of up to 30 years and fines of $250,000.