Doubts arose on Sunday over the authenticity of the shocking photos after military sources quoted by the BBC said many aspects of the pictures were suspicious.
The British military has launched an investigation into photographs published on Saturday in Britain's mass-circulation Daily Mirror newspaper, appearing to show troops beating and urinating on a hooded Iraqi prisoner in a camp near Basra in British-controlled southern Iraq.
The Daily Mirror said the prisoner, aged between 18 and 20, was savagely beaten before being thrown from a moving truck.
However, Britain's national broadcaster said unnamed sources close to the Queen's Lancashire Regiment - members of which allegedly leaked the photos - believed several aspects of the pictures made them implausible.
The rifle appeared to be an SA80 mk 1, which was not issued to soldiers in Iraq. Troops wore berets or hard hats, not the floppy hats as seen in the pictures. The truck in the photo also appeared to be a type never used in Iraq.
British Prime Minister Tony Blair condemned the photos as "completely and utterly unacceptable".
Daily Mirror editor Piers Morgan said he stood by the story and hinted at more revelations to come after "sensational interviews" with the soldiers who provided the images.
"... people were literally getting serious, serious beating or kickings when they were plasticuffed - you're talking broken ribs, punctured lungs sort of thing"
"We told the truth" the paper's Monday edition quoted the two British soldiers as saying.
"We stand by every single word of our story," they told the paper under cover of anonymity.
"This happened, it is not a hoax and the army knows a lot more has happened," the pair were quoted as saying.
The anonymous sources added that the British army knew there were other pictures of similar incidents of prisoner abuse in Iraq.
British Foreign Secretary Jack Straw appeared to leave the door open to possible compensation for any victim, though he stressed it was too early to prejudge the outcome of an inquiry underway.
"Of course it follows that we will accept whatever obligations there are upon us," he told BBC television.
British Prime Minister Tony Blair
condemned the photos
"These allegations are taken extremely seriously and they will be investigated thoroughly."
The publication of the photographs in Britain came after pictures broadcast throughout the world, appearing to show US soldiers abusing Iraqi prisoners, drew condemnation from international leaders.
Meanwhile, fresh claims emerged of mistreatment of Iraqi detainees by British troops.
The television programme GMTV, on Britain's independent ITV channel, read out an account of an anonymous officer serving in the British army saying that abuse of Iraqi prisoners "was definitely heard of".
Fellow officers were "hugely annoyed and upset about it", he said.
He added: "People were literally getting serious, serious beating or kickings when they were plasticuffed - you're talking broken ribs, punctured lungs sort of thing."
The former chief of the group of experts responsible for finding weapons of mass destruction in Iraq, David Kay, also waded into the debate, suggesting the photographs lent weight to calls for occupying troops to withdraw.
"We are clearly at a crisis point," said Kay, who resigned in January saying there were no stockpiles of weapons of mass destruction in Iraq.
Occupying troops must decide whether to stay in the country or accept they were "becoming the issue" and withdraw, he said.