WASHINGTON, May 6: Lynnadie England, a 21-year-old American soldier, drags a naked Iraqi prisoner with a leash tied around his neck while the man attempts to keep his head above the floor.

This is one of 1,000 new digital pictures that surfaced in the United States on Thursday, many of them showing US soldiers abusing Iraqi prisoners. Newspapers that published only a few of these pictures said some were too grotesque to print.

The Washington Post published four of these pictures, including the one of Lynndie dragging her prisoner, which dominates the upper half of the front page. Another picture shows a naked Iraqi man with a dark hood over his head, handcuffed to a cell door.

A third shows a naked man handcuffed to a bunk bed. His arms splayed so wide that his back is arched and a pair of women's underwear covers his head and face.

Yet another picture shows a group of naked men bound to one another on the walkway of a dormitory at Abu Ghraib prison while three US soldiers give them instructions.

The pictures revived calls for US Defence Secretary Donald Rumsfeld to resign and for President George W. Bush to apologies to the Iraqi nation. The Washington Post said some of the pictures might have been staged but others are real.

The Post also published a message from Lynndie to her mother, saying: "Mom, I was in the wrong place at the wrong time." Some of her friends and relatives, however, said she could not have been involved in such a horrible act and the picture was faked.

Her father Kenneth England said other soldiers would force his daughter to pose for photographs and "that's how it happened." Also on Thursday, the International Red Cross said it had repeatedly asked US authorities to take action over reported abuses at Abu Ghraib prison before the recent revelations.

Spokeswoman Nada Doumani said Red Cross representatives had visited the prison and spoken privately with detainees. "We were aware of what was going on, and based on our findings we have repeatedly requested US authorities to take corrective action."

As the new pictures and reports of more abuses reached the American public, a powerful Midwestern newspaper, the St. Louis Post-Dispatch, demanded: "Rumsfeld should resign and take his top deputies with him."

"There's a lot of explaining that Secretary Rumsfeld and others have to do, including why Congress was never informed," said John McCain, a Republican senator from Arizona.

Lawmakers have summoned Mr Rumsfeld to Capitol Hill on Friday to testify. Both Republican and Democratic senators are working on a resolution to condemn the abuses.

Meanwhile, the US Army has acknowledged that at least a dozen deaths at prisons and detention camps remained under scrutiny by criminal investigators. The CIA's inspector-general was also looking into three deaths that may have involved agency officers or contractors.