Inmates of an Ohio prison secretly built computers, which they used to download porn and research how to commit credit card fraud, it has been discovered.
The state's Inspector-General released a report on Wednesday (NZ time) detailing the incredible find.
Marion Correctional Institution only uncovered the two machines when the prisoners' heavy internet use was detected by the prison's IT department.
The clever hackers built the computers using parts from a prison computer skills programme. In addition to porn, the inmates had installed anti-virus software, privacy software such as the encrypted TOR browser and a virtual private network, and hacking tools.
They'd been using the prison's internet connection undetected for four months. Once staff began to suspect something was up, it took them three weeks to find the computers, which were hidden above a training room closet in a section of the prison inmates weren't allowed to go in unsupervised.
"Articles about making home-made drugs, plastics, explosives, and credit cards were discovered," the report reads.
One prisoner admitted smuggling in porn and new release movies on flash drives, which he'd sell to his fellow inmates.
The inspector-general told local media that the prisoners were able to build something so complex without being found for months was an embarrassment.
"They were able to travel through the institution more than 1100 feet without being checked by security through several checkpoints, and not a single correction's staff member stopped them from transporting these computers into the administrative portion of the buildin image" Randall Meyer told WSYX.
"It's almost if it's an episode of Hogan's Heroes."
The five prisoners behind the scheme have since been transferred to other institutions.