Amid calls for US Secretary of Defence Donald Rumsfeld's resignation, the Pentagon plans to show unseen evidence of brutality against Iraqi prisoners, including serious charges like rape and murder, at Abu Ghraib prison to members of Congress.

Faced with worldwide condemnation over the issue, the defence secretary is also mulling over the possibility of monetarily compensating the Iraqi prisoners who have been wronged, a media report quoting senior Pentagon officials said on Monday.

Testifying before the Senate Armed Services Committee last week, Rumsfeld had said Pentagon has obtained more photos and video footage that show US troops engaged in even worse behaviour. 

"We're not just talking about giving people a humiliating experience. We're talking about rape and murder and some very serious charges," Senator Lindsay Graham was quoted as saying by Time magazine.

"Rumsfeld is more shaken than in any previous crisis," the report said quoting a senior Pentagon source.

"He's not a man of self-doubt," said the official, but he's "questioning himself and others more rigorously than previously".

"Practices employed at Abu Ghraib may be more widespread than the US has acknowledged," Time said in its lead story 'The Scandal's Growing Stain'.

One US official is quoted as saying that some Federal Bureau of Investigation agents were well aware that the military was using "very aggressive" interrogation methods that would not be condoned in the US.