An investigation was launched following claims that an Iraqi prisoner of war was beaten to death by a British soldier, the Ministry of Defence said.
The victim suffered at least 50 injuries, according to a report today.
A Ministry of Defence spokeswoman confirmed it was making inquiries after a PoW died while in the custody of British forces but described reports that a British soldier would be charged with manslaughter as "pure speculation".
She declined to give any details about the alleged injuries suffered by the man, reportedly named Mr Al-Maliki.
The victim was allegedly captured by troops from the Queen's Lancashire Regiment who swooped on pro-Saddam bandits near the British-held city of Basra last September.
He was among nine others taken to an army base in the city, according to The Sun.
One later died and was said to have a huge number of internal and external injuries, said the paper.
A second PoW was severely beaten and suffered kidney failure, a third suffered serious internal injuries and the other six all lodged complaints about their treatment, the paper said.
The MoD confirmed the Royal Military Police Special Investigations Branch, which handles the most sensitive cases, was conducting the inquiry into how the Iraqi died.
The Queen's Lancashire Regiment is in Iraq on peacekeeping duties.
A month before the Iraqi died they had lost one of their number after coming under attack.
Captain Dai Jones, 29, of 1st Battalion, QLR was killed on August 14 in a bomb attack on a military ambulance in Basra.
Married Capt Jones, from Louth in Lincolnshire, had been working on civil-military cooperation projects to reconstruct the city.
The spokeswoman for the Ministry of Defence said: "I can confirm an Iraqi prisoner of war has died while in the custody of UK forces.
"A Royal Military Police Special Investigations Branch investigation into the death of Mr Al-Maliki is ongoing and it would be inappropriate to speculate about its outcome.
"The investigation is a thorough one, involving interviews in Britain and Iraq and this inevitably will take time.
"If British soldiers are found to have acted unlawfully, appropriate action will be taken.
"Any suggestion soldiers will be charged with manslaughter is pure speculation at this stage."Reuse content