THREE US prison guards have been charged after allegedly organising a wrestling match between inmates in a storage closet, among a series of cruel challenges one prisoner labeled the "retard Olympics".

The three men are also accused of asking inmates at York County Prison to drink a gallon of milk in one hour - popularly known to cause vomiting - or accept being sprayed in the face with pepper foam, according to Pennsylvania’s Patriot-News.

The newspaper, citing state police, says inmates at facility in York, an hour west of Philadelphia, would be offered food and coffee as rewards for completing the challenges.

The three guards - David Whitcomb, 28, Mark Haynes, 26, and Daniel Graff, 37 - have been criminally charged with official oppression and have been placed on unpaid administrative leave, the prison said.

David Wright, an inmate who says he was involved in one of the alleged wrestling matches, told investigators Haynes and Graff arranged for him to wrestle another prisoner, James Hicks, in a closet.

He said the rules of the match were that there would be no punching to the face and the winner would be whoever made the other "tap out," or give up.

Hicks, who said the challenges were consensual, also detailed other feats allegedly enourgaed by the guards: snorting crushed up lollies, drinking a bottle of water with pepper foam in it and eating fruit with the peels still on them.

"The actions alleged by Pennsylvania State Police in this case run counter to the professional behavior County and Prison management expect and require of all staff," the York Country Prison said in a statement. "Misconduct within any County agency is not tolerated."