BULFORD CAMP, England - A British soldier pleaded guilty on Tuesday to committing a war crime by inhumanely treating detainees while serving in Iraq.

British troops patrol their base in southern Iraq, in 2005. A British soldier became the first ever member of the country's armed forces to admit to a war crime, as prosecutors listed alleged "systematic abuse" of civilian detainees in Iraq. [AFP]

Corporal Donald Payne is one of seven British soldiers facing court martial over the death in custody three years ago of an Iraqi hotel receptionist in the southern city of Basra.

Five of the seven were serving with the Queens Lancashire Regiment while two others were with the Intelligence Corps at the time of the death of Baha Musa after his arrest by a British patrol six months after 2003 the U.S.-led invasion of Iraq.

The men face an array of charges from manslaughter to negligence.

Musa, the court heard, had 93 injuries on his body, including a broken nose and ribs, while another man was so badly beaten that he nearly died from kidney failure.

All were held in a raid on a hotel in Basra as the insurgency grew. Guns, grenades, ammunition, bayonets and a sniper scope were found in the raid.

Britain, Washington's main ally in Iraq, has investigated scores of deaths and injuries of Iraqis since joining the war.

Three UK soldiers were jailed in February 2005 for abusing Iraqi detainees in a case which drew comparisons with the mistreatment of Iraqis by U.S. troops at the Abu Ghraib prison.

Chief among the accused is Payne, 35, charged with the manslaughter of Musa, inhumane treatment of prisoners and trying to pervert the cause of justice by getting people to lie about the cause of death.

"SYSTEMATIC ABUSE"

Opening the prosecution case against him, Julian Bevan accused Payne -- a military policeman in charge of the detainees -- of beatings, sleep deprivation and forcing the men to stand for hours in extremely painful positions.

"We are dealing in this case with systematic abuse against prisoners involving unacceptable violence against persons who were detained in custody, hooded, handcuffed and wholly unable to protect themselves," he told the 7-man court martial panel.

He accused Payne of being mainly responsible for the abuse, which included tweaking of nipples, punching and forcing the drinking of urine.

In court on Tuesday, Payne pleaded guilty to inhumane treatment of Iraqi detainees -- a war crime -- but not guilty to the other two charges.

Also in court were Sergeant Kelvin Stacey, 29, charged with assault causing actual bodily harm, Lance Corporal Wayne Crowcroft, 22, and Private Darren Fallon, 23, charged with the inhumane treatment of detainees.

Major Michael Peebles, 35, and Warrant Officer Mark Davies, 37 -- both of the Intelligence Corps -- and Commanding Officer Colonel Jorge Mendonca are all charged with negligently performing a duty by failing to stop the abuse.

All six pleaded not guilty.

In pre-trial hearings, Judge Stuart McKinnon ruled that no pictures or images of the accused nor details of their home addresses or locations may be published for fear of revenge attacks on themselves or their families.

The high-profile trial at the Bulford army camp near Salisbury, some 70 miles southwest of London, is expected to last up to four months.