A federal inmate, in prison for money laundering and drug conspiracy, pleaded guilty Tuesday to conspiracy to escape from a prison camp to meet his fiancee for sex — one of three convicts caught leaving the property since February.

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While a sexual encounter was the reason Deldrick Jackson climbed a fence and then walked out of the camp adjacent to the U.S. Penitentiary on McDonough Boulevard in southeast Atlanta late April 13, federal agents say Jackson and fiancee Kelly Bass had been operating an inmate taxi service for several months, collecting about $4,000 from prisoners who allegedly paid for rides in Bass' SUV to nearby restaurants, motels and homes. Bass has pleaded not-guilty to helping Jackson escape, and the Stone Mountain mother of three is free on bond.

The inmate escaped from the courthouse, picking his handcuff-lock while on a bathroom break, and was found by firefighters along the Etowah River in the dark of the night.

On that night, Assistant U.S. Attorney Jeff Davis said Jackson and Bass had just visited a fast-food restaurant near the prison. Authorities found in Bass’ silver Acura SUV two cellphones, 83 packages of cigarettes and eight bottles of Canadian Mist whiskey, all items that are banned in prison.

Jackson was already serving a sentence of 10 years and 10 months and was scheduled to be released on Jan. 14, 2022, until this arrest. He will be sentenced Aug. 29 and could get as much as five years added to his time in prison.

Jackson is the second inmate to plead guilty to escape, at least temporarily, that has been detailed in court filings about a sophisticated and extensive operation at the minimum-security prison involving inmates cutting holes in fences or climbing fences to retrieve cell phones, drugs, alcohol, takeout food and other items to be sold to fellow convicts.

Justin Stinson was the first to be caught. Stinson pleaded guilty last month. Until he was charged with escape, Stinson was scheduled to be freed from prison at the end of next year, but now he could get five years more added to his time when he is sentenced next month.

Stinson had a duffel bag containing a cellphone, scissors, two 1.75 liters of Jose Cuervo tequila, two cartons of Newport cigarettes, four boxes of Black and Mild cigars and food items. He told the judge he picked up the bounty because he wanted cigarettes to feed his nicotine habit.

A third inmate was arrested last week in a wooded area just off the prison property. Fernando Settles, who is serving 20 years for "conspiratorial and substantive drug trafficking," was caught during the early-morning hours of May 8 with a cell phone and an empty duffel bag, according to a FBI agent's affidavit.

Since Stinson's arrest 3 1/2 months ago, The Atlanta Journal-Constitution has reported on the inmate-run black market operation at the prison that is surrounded by businesses, homes and apartment complexes, using details provided by inmates and in court records.

Though the first arrest was made in February, for at least three years inmates at the prison camp have been temporarily escaping but returning with contraband to sell to other convicts. They have brought in cocaine and marijuana, beer and tequila, Mexican takeout and food for barbecuing.

One inmate, who spoke on the condition of anonymity because of concerns other prisoners or officers will retaliate, told the AJC inmates were able to have parties, to smuggle in contraband and to drink until they passed out because usually there is only one — but sometimes two — officers assigned to watch almost 500 inmates housed in eight buildings.

On Saturday, the warden over the camp and the much-larger medium-security prison next-door suddenly and unexpectedly retired.

According to the president of the union that represents correctional officers, former warden Darlene Drew had been off last week and came in only to call an emergency staff meeting to announce she was retiring. Union president Vance Bryant said she did not take questions and did not elaborate beyond saying she was bringing an end to her 32-year career with the Bureau of Prisons.

The Bureau of Prisons in Washington has not responded to numerous emails seeking comment on the escape problem at the prison camp.