Guantanamo force-feeding techniques revealed

Leaked document details new policy after recent protests and is the most detailed description of hunger striker treatment to date

Contains first published details of restraint chairs used to force feed prisoners

Final authority over who gets force-fed lies with Guantanamo commander as opposed to a medical professional

Identities of prisoners who are force fed shared with top Pentagon officials

Prisoners are given powerful drugs during force feeding

Document notes hunger striking prisoners should be isolated so they don't achieve solidarity

Doctors and nurses do not act independently and appear to be violating medical ethics. They are an apparatus of the security force and carry out the policy

Al Jazeera has exclusively obtained classified information which shows hunger striking Guantanamo prisoners are being force-fed a liquid nutritional supplement through a brutal and dehumanising medical procedure that requires them to wear masks over their mouths while they sit shackled in a restraint chair for as long as two hours.

The prisoners remain this way, with a 61cm tube - or longer - snaked through their nostril until a chest X-Ray, or test dose of water, confirms it has reached their stomach.

Information on the restraint system, obtained exclusively for the first time by Al Jazeera, along with the feeding procedures policy, was contained in a newly revised Standard Operating Procedure (SOP) for Guantanamo hunger strikers from United States Southern Command (SOUTHCOM), which has oversight of the joint task force that operates the prison.

The 30-page SOP contains the most detailed descriptions to date pertaining to the treatment of hunger strikers and prisoners who undergo force-feedings. The SOP replaced a previous SOP issued in 2003 (revised in 2005) which was declassified several years ago by the Pentagon with redactions. The new, unredacted policy obtained by Al Jazeera went into effect March 5 - one month after Guantanamo prisoners launched their protest over the inspection of their Qurans.

The SOP appears to have been revised and implemented in order to deal with a mass hunger strike which is taking place.

Journalist Jason Leopold, who obtained the documents, found out that, after a prisoner is identified as a possible hunger striker, a medical officer performs a physical and psychological evaluation. The prisoner is then 'counseled' about the dangers associated with a hunger strike.

'If detainee continues to hunger strike and clinical criteria for the initiation of enteral feeding are met the detainee may be admitted to the Detention Hospital or designated feeding block if medically stable. Authorisation is obtained via chain-of-command from JTF-GTMO Commander to begin enteral feeding.'

Before being placed into the restraint chair, medical personnel offers the prisoner one last chance to eat voluntarily. If the prisoner refuses, the 'medical provider signs medical restraint order' to force feed the prisoner and encourages him to use the restroom before he is shackled.

The guard force then 'shackles detainee and a mask is placed over the detainee's mouth to prevent spitting and biting,' states the chair restraint protocol. 'Detainee is escorted to the chair restraint system and is appropriately restrained by the guard force.'

Al Jazeera has found out currently there are 23 prisoners who are being force-fed. Long-term hunger strikers who are force-fed, or as the SOP describes them, 'chronic enteral feeders,' 'are notified by staff that 'It is time to feed.'