Hardin crafted a fake police uniform, which helped him escape prison when he ordered a guard to "open the gate" to a parking lot outside.
Officials are still figuring out how an ex-police chief escaped from an Arkansas prison earlier this year by allegedly dressing up as a law enforcement officer, ordering a prison guard to "open the gate" to a parking lot, and easily walking out of custody.
The inmate, 56-year-old former Gateway, Ark., police chief Grant Hardin, evaded police for 10 days in late May before he was recaptured in early June and sent back to prison -- this time charged with escaping prison. He pleaded not guilty.
Hardin, who was the subject of HBO's 2023 Devil in the Ozarks docuseries, had already been in prison serving a 30-year sentence for murdering a fellow Gateway city official and two 25-year sentences for rape. He was initially sentenced in 2017.
According to documents from a Critical Incident Review by the Arkansas Department of Corrections, police have interviewed Hardin at least five times about his plot since he was recaptured on June 6, and have gradually begun to piece together details about his escape.
Hardin allegedly told officials he was able to fashion a makeshift police uniform, which fooled other prison guards into allowing his escape. CNN first published the Arkansas Department of Corrections report, which was also reviewed by PEOPLE.
The report alleges Arkansas prison officials have learned that Hardin was planning the escape for six months and that he was able to procure the materials he used to make his fake police uniform while working unsupervised in the prison's kitchen.
"Prior to the escape, he started preparing his clothes by using black markers (Sharpies) he had taken from the kitchen and laundry which he found lying around because staff were not keeping up with them," according to the report. The report says Hardin wore "what appeared to be an officer's stab vest [which] had the word POLICE on the back" and was made out of black kitchen aprons. He also wore a fake silver metal police badge made out of "the top of a kitchen can that food comes in," which he was able to mold into the shape of the badges worn by other prison officials.
Per the report, prisoners working in the kitchen at the North Central Unit in Calico Rock, Ark., were often left unsupervised when they went out onto the kitchen's back dock. There, it is believed Hardin was able to change and walk away from his post undetected.
Prison security footage from soon after shows Hardin "pulling a cart, wearing altered clothes (died black), a vest, and a black hat," according to the report. "The cart contained what appeared to be a home-made ladder made of pallets and a box," the document adds.
According to the report, Hardin "was going to use [the materials] as a ladder to go over the fence," but instead stuck to a different plan when he simply "walked up to the gate he just directed the officer to 'Open the gate,' and he did."
"Hardin went to the ICC building and pretended to place something in a vehicle parked in the area then went behind the building and crossed the road to Deputy Warden's house and down a trail into the woods," the report continues.
Hardin is believed to have hid in the woods for the next week and a half.
"He ate whatever he could find including berries, bird eggs and ants," the report says, adding that he drank water from a creek, as well as from a CPAP machine he stole from the prison infirmary.
The ex-police officer denied having help from other inmates or prison officials, though authorities say the half-dozen interviews he's given since his return to prison have been lacking the total detail officials have desired. "Inmate Hardin was inconsistent and deceptive in answering all questions," the report says.
Ultimately, Hardin allegedly told officials he planned to hide in the woods "for six months if need be and begin moving west out of the area" once the pressure from search teams died down. However, Hardin "began to get very hungry and concerned about how close the search teams consistently were getting to him," leading to him to try and move out of the area less than two weeks into his six-month plan, ultimately getting him caught.
The Arkansas DOC report says that "it is obvious there was a lot of confusion" among prison officials while responding to Hardin's escape on May 25, adding that a number of disciplinary actions and changes to security have since been recommended or put in place since the escape and 10-day manhunt. CNN reports that two prison employees have since been fired.
A spokesperson for the Arkansas DOC did not respond to PEOPLE's request for comment Monday.