TWO Iraqi prisoners have been murdered by Americans, US officials admitted yesterday as an internal investigation by the US Army exposed “sadistic, blatant and wanton criminal abuses” of Iraqi prisoners.

US politicians conceded that the unfolding story of maltreatment at Abu Ghraib prison had dealt a big blow to the coalition. Edward Kennedy, the Democratic Massachusetts senator, emerging from a private briefing with military officials, said the abuse at Abu Ghraib did not appear to be an isolated incident. He said that there were reports of further mistreatment in Iraq and Afghanistan.

The American authorities in Baghdad responded to the latest revelations by announcing last night that it would halve the 3,800 population of Abu Ghraib, which is at the centre of the abuse allegations.

One US soldier has been convicted by the military behind closed doors of killing a prisoner by hitting him with a rock, officials said. He was reduced in rank to private and discharged from the service but did not serve any time in jail. A private contractor working for the CIA was also found to have killed a prisoner.

Military officials disclosed that there have been 35 criminal investigations into claims of prisoner abuse and deaths in Iraq and Afghanistan since December 2002. Ten investigations into deaths and ten into assaults are under way, Major-General Donald Ryder, the Army’s Provost Marshal, said.

The cause of 12 other deaths at US-run prisons in Iraq and Afghanistan were ruled to be undetermined or natural. Another death was ruled a justifiable homicide.

The internal report, marked “Secret, no foreign dissemination”, but seen by The Times, details at least 20 ways in which American guards at Abu Ghraib had abused detainees. It is backed up by photographs and confessions and concludes that soldiers have “committed egregious acts and grave breaches of international law”.

The internal inquiry, led by Major-General Antonio Taguba, was started at the end of January and reported in secret at the beginning of March. The report, a copy of which has been obtained by The Times, catalogues the sadistic treatment inflicted on detainees. General Taguba concluded that the abuse was “systemic and illegal”, and “intentionally perpetrated” by officers from the 800th Military Police Brigade.

The abuse, which the report says was inflicted on detainees in the cell block used by Military Intelligence, included:

Using military working dogs to frighten and intimidate detainees with threats of attack, and in one instance actually biting a detainee.

The intentional abuse of detainees by military police personnel included:

Writing “I am a Rapist” on the leg of a detainee alleged to have raped a 15-year-old fellow detainee, and then photographing him naked.

General Taguba said he found the charges “credible, based on the clarity of their statements and supporting evidence provided by other witnesses”.

General George Casey, the Army Vice-Chief of Staff, said: “It is a complete breakdown in discipline.”

Donald Rumsfeld, the Defence Secretary, said the Pentagon would do everything to bring to justice “those that may have violated the code of military conduct and betrayed the trust placed in them by the American people”.

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