US Defence Secretary Donald Rumsfeld has flown into Abu Ghraib prison during his surprise visit to Iraq today.
The embattled secretary, travelling under tight security to a country where more than 700 US troops have died since last year, earlier landed at Baghdad airport and held meetings with senior US military officers in the capital.
During his half-hour tour of the prison in an armoured bus, most of the 3,000 prisoners kept in razor-wire compounds looked on impassively, but some shook fists or gave thumbs-down signs.
"We told ourselves that the right thing to do was to come out here and look you folks in the eye," Mr Rumsfeld told US guards in the prison mess hall after meeting Major General Geoffrey Miller, the new commander in charge of jails in Iraq.
"In recent months the things that happened at this base happened under our responsibility and it has been a body blow for all of us...Don't let anyone tell you that America is what's wrong with the world because it's not," he said. "We will get through this tough period, no doubt about it."
Mr Rumsfeld denied on a 15-hour flight from Washington he was trying to cover up the scandal at Abu Ghraib jail near Baghdad. "If anybody thinks that I'm (in Iraq) to throw water on a fire, they're wrong," he told reporters aboard his aircraft. "We care about the detainees being treated right. We care about soldiers behaving right. We care about command systems working."
Mr Rumsfeld has rejected calls from newspapers and some opposition Democrats to resign.
Major General Miller, who previously ran the US military prison at Guantanamo Bay in Cuba, said he had totally reorganised the operation of Abu Ghraib, partly by separating the units responsible for overseeing incarceration from those responsible for intelligence and interrogation.
"I am absolutely convinced that we laid down the foundations of how you detain people in a humane manner. And it is unequivocal in its explanation," he said.
The abuse scandal has ignited international outrage and shaken US global prestige as the United States seeks to stabilise Iraq and President George W. Bush seeks re-election.
Mr Rumsfeld has warned more damaging photographs, which members of Congress reviewed yesterday, have yet to be made public.
Emerging form a closed session of the Senate Armed Services Committee, members struggled for words to describe their feelings after viewing new images of violence and sexual humiliation from Abu Ghraib. One member desccribed he experience as a descent into "the wings of hell".
Images show inmates apparently being coerced to commit sodomy, wounds possibly from dog bites, and a number of dead bodies.
"When you think of the sadism, the violence, the sexual humiliation, after a while you just turn away, you just can't take it any more," said Democrat Senator Richard Durbin.
As Mr Rumsfeld arrived in Iraq, there was renewed fighting in the holy cities of Najaf and Kerbala, where US troops are facing an uprising by a Shia Muslim militia loyal to radical cleric Moqtada al-Sadr.
Sadr's Mehdi Army fighters stormed the main police station in Najaf overnight, held the police chief hostage and emptied the weapons store, police said. They made off with three police vehicles when US tanks arrived at the station.
In nearby Kerbala, gunfire echoed from narrow streets just a few hundred yards from the revered Imam Hussein mosque in early afternoon. A Reuters cameraman said militiamen had attacked a US Abrams tank with rocket-propelled grenades and damaged it.
Agencies