Two soldiers who gave the Daily Mirror photos apparently showing UK troops torturing an Iraqi captive stand by their story, the paper's editor says.
The paper claims British soldiers handed over the photos
The Queen's Lancashire Regiment members also have a number of "serious new allegations", Piers Morgan added.
Army sources raised doubts about the veracity of the images while Tory defence spokesman Nicholas Soames questioned the decision to print them.
Mr Morgan said he made no apology for exposing "this outrageous behaviour".
He added that the alleged abuse had been "common knowledge among disgusted British servicemen in Basra for months".
The pictures show a hooded man being urinated on, a boot placed on his head, and a rifle butt in his groin.
"These soldiers felt compelled to expose what went on because they believed it was fundamentally wrong, and that it would inevitably be reported at some stage," Mr Morgan said.
"As General Sir Michael Jackson made clear, the people that carried out these sickening acts simply have no place in the British Army."
But Mr Morgan was keen to point out that the paper believed the majority of troops in Iraq had been carrying out an "outstandingly brave job".
An investigation has begun into the claims, also carried in the Mirror, that British troops assaulted the prisoner before throwing him from a lorry.
Tony Blair said if the photos were authentic this was "completely and totally unacceptable".
Mr Soames said: "One has to wonder at the behaviour of the Mirror in publishing these pictures where there is clearly a question mark over their veracity.
"These pictures... will have made the life of British forces on the ground in Basra even more difficult than it is already.
"We need to be a little more cautious before rushing to judgement."
BBC defence correspondent Paul Adams says sources close to The Queen's Lancashire Regiment are suspicious of some details in the photographs.
He says they believe they may not even have been taken in Iraq.
They believe the rifle is an SA80 mk 1 - which was not issued to troops in Iraq.
They say soldiers in Iraq wore berets or hard hats - and not floppy hats as in the photos.
They also believe the wrong type of Bedford truck is shown in the background - a type never deployed in Iraq.
Our correspondent said the regiment concerned had suffered a difficult tour in Iraq, with charges expected in the case of a man beaten to death in custody.
Colonel Bob Stewart, who commanded British forces in the Balkans, told BBC News Online he could not say whether the photos were genuine.
As well as questions over the equipment, he said there were also discrepancies over clothing and the captive's condition.
"The shirt looks like a football shirt. Is that the sort of shirt that a captive might be wearing, slightly silky with an Iraqi flag?
"Why is it not dirty and dishevelled, why is the man not showing some signs of damage after eight hours of beatings?
"Why would the soldiers be wearing webbing that is undone? Normally soldiers are very particular about that."
But Colonel Stewart said regardless of the pictures' authenticity, the damage done to Iraqi and Arab opinion would act as a recruiting sergeant for insurgents.
"What happens to the next British soldier who is taken hostage?"
The images have already been seen in the Middle East
Foreign Secretary Jack Straw told the BBC's Breakfast with Frost programme: "There is a very high-level investigation taking place. The allegations are terrible."
But he would not say whether any victims of maltreatment would be offered compensation.
"Of course... we will accept whatever obligations there are upon us."
Army spokesman Roger Goodwin, on behalf of The Queen's Lancashire Regiment, said: "Whether the soldiers involved in the alleged atrocities were members of the QLR needs to be established.
"There is no place in our regiment for individuals capable of such appalling and sickening behaviour."