The US government has covered up the death of three Guantanamo detainees who have died from torture during interrogation but were pronounced as suicides, the Harper magazine reports in its March edition.

"The cover-up is amazing in its audacity, and it is continuing into the Obama administration," writes contributing editor Scott Horton.

Three Guantanamo detainees, two Saudis and a Yemeni, were pronounced dead in June 2006.

American authorities said that the detainees had committed suicide at the detention camp.

"The official story... was full of unacknowledged contradictions," charges the US magazine.

It claims that a 1700-page report by the Naval Criminal Investigative Service (NCIS) on the deaths shows that suicide was not the main cause.

"The centerpiece of the report – a reconstruction of the events – was simply unbelievable," says the magazine.

"Each prisoner was able somehow to bind his own hands, and, in at least one case, his own feet, then stuff more rags deep down into his own throat.

"We are then asked to believe that each prisoner, even as he was choking on those rags, climbed up on his washbasin, slipped his head through the noose, tightened it, and leapt from the washbasin to hang until he asphyxiated."

Detainees and human rights advocates have reported torture and abuse in Guantanamo, including physical abuse, waterboarding and sleep deprivation.

There have been reports of degrading and sadistic treatment of detainees at the infamous detention centre, which has been globally condemned as a stain on America's human rights record.

The US has been holding hundreds of detainees at the detention center for years, branding them unlawful enemy combatants to deny them legal rights under the American legal system.

Black Sites

Former Guantanamo guards have confirmed to the magazine that the detainees died in one of the camp’s "black sites", not in their cells.

Joe Hickman, then a sergeant at the camp, confirmed that no prisoners were transferred from camp 1 (where their cells were) to the clinic as cited in the NCIS report.

But he recalls a vehicle moved from "Camp No," so called because there was no information about who is inside even to the guards, to be backed up to the entrance of the medical clinic, as if to unload something.

Hickman remembers that immediately after that the camp suddenly lit up - stadium-style flood lights were turned on – amid frenzied activity.

He went to the clinic with his friend Specialist Tony Davila.

"One of them was severely bruised," Horton quoted a medical corpsman as saying.

"Davila told me he spoke to Navy guards who said the men had died as the result of having rags stuffed down their throats."

-- in put from agencies