Charged in a five-count federal grand jury indictment were Jacob Belford, 29, originally from Reno, Nev.; James Brooks, 26, originally from Lufkin, Texas; and Sophia Kiiti, 26, of Reno, Nev.
They are charged with conspiring to smuggle methamphetamine into the prison, according to a statement released by the FBI from United States Attorney Benjamin B. Wagner.
"According to the indictment," the FBI said, "Belford and Brooks are inmates and conspired with Kiiti to have methamphetamine mailed to Belford and Brooks and another inmate at the Atwater Penitentiary. Kiiti concealed the methamphetamine under a label on a piece of correspondence sent to the prison."
Investigating the case were the FBI and the Bureau of Prisons.
Convictions could result in a maximum statutory penalty of 20 years in prison.
"Any sentence, however, would be determined at the discretion of the court after consideration of any applicable statutory factors and the Federal Sentencing Guidelines, which take into account a number of variables," the FBI said.