(CNN) -- Inmates at a prison in Cuba have made a set of hidden-camera videos to expose the conditions there, publicizing the filth and decrepitude of the facilities despite the risk of retribution.
"The conditions here at Combinado del Este are subhuman, and the food is unfit for human consumption," says inmate Douglas Moore, who says he is an American convicted of a drug offense.
Because he is an American, he says in the video, "I am singled out for abuse. I cannot count all the times that I have been chained by my hands and legs and beaten mercilessly, then robbed of my meager possessions by the guardia frontera here at Combinado del Este."
He pulls up his pants to show bruises on his leg, and is seen walking with a cane. He points out his cracked and broken sink, and then shows how his toilet is too broken to sit on, so if he wants to use it he has to place a chair frame over it.
The videos -- obtained by CNN through a dissident journalist -- show derelict cell blocks overlooking a seedy exercise yard. The grime on the walls is so thick that when an inmate wipes it with a napkin, the paper becomes blackened with filth. Some of the toilets shown are barely more than a hole in the floor.
Prisoners, including the narrator, complain in Spanish of dubious food, meager rations, dilapidated cells, moldy walls, overcrowding, and limited exercise hours. They say sewage leaks are persistent.
Combinado del Este is a Cuban maximum security prison about 10 miles southeast of Havana. It is believed to hold both ordinary prisoners, like violent criminals and drug runners, as well as political prisoners jailed for criticizing the ruling Castro brothers.
Representatives of the Cuban government in Havana, Washington, and New York did not respond to requests from CNN for comment.
The International Committee of the Red Cross said it is unable to investigate conditions at Combinado del Este. "Unlike in many other countries in the region," said spokesman Steven Anderson, "the ICRC does not have access to prisons in Cuba."
But photos from a media tour of the prison in 2004 depicted a far rosier picture, with inmates being taught computer skills and exercising on a lawn.
CNN cannot verify the authenticity of the videos, obtained through Dania Virgen Garcia, a dissident journalist in Cuba whose blog is called Cuba por Dentro. Two of the 10 videos are posted on a YouTube channel associated with Cuban dissidents. Her blog address is shown on the videos. Garcia said the footage was shot in January using a camera smuggled into the prison.
The prisoners who made the tapes may be in danger of retribution, according to Frank Calzon, a Castro critic who is executive director of the Center for a Free Cuba. But this month's visit to Cuba by the pope may shield them from retribution, at least in the short term, he said. And in the long term, he added, the prisoners may believe it is worth the risk to make the videos and publicize their conditions.
"The only hope a prisoner has," he said, "is for the outside world to know about their plight. Getting attention is a way of forcing the government not to mistreat you."
CNN's Javier de Diego and Patrick Oppmann contributed to this report