Iraqi security forces systematically abuse prisoners, a leading US-based human rights group reports.
International advisers are accused of turning a blind eye to abuses
Unlawful arrests, torture and the long-term isolated detention of detainees - including children - are "routine", Human Rights Watch says.
Of 90 prisoners interviewed by the group since 2003, 72 said they had been abused by the new Iraqi authorities.
HRW acknowledged Iraqi security forces were targeted by insurgents but said this did not justify prisoner abuse.
Executive director for HRW Sarah Leah Whitson said Iraqi forces and international advisers were allowing abuses to "go unchecked" in the name of bringing stability to Iraq.
She said: "The people of Iraq were promised something better than this after the government of Saddam Hussein fell.
"The Iraqi interim government is not keeping its promises to honour and respect basic human rights.
"Sadly, the Iraqi people continue to suffer from a government that acts with impunity in its treatment of detainees."
Among the alleged abuses detailed in the 94-page report:
- Detainees were routinely beaten with cables and metal rods during interrogation, given electric shocks and kept blindfolded and handcuffed for days
- Detainees were held for long periods in isolation, deprived of food and water and crammed into small cells with standing room only
- Iraqi police sought bribes in return for releasing prisoners or allowing them access to family members or food and water.
Some prisoners suffered what may be permanent disability as a result of their treatment, the New York-based group says.
The report - The New Iraq? Torture and ill-treatment of detainees in Iraqi custody - found evidence of widespread human rights violations against alleged national security suspects and common criminals since 2003.
It also highlights "serious violations" by the Iraqi intelligence service since mid-2004 against members of political parties judged to be a threat.
Between July and October 2004, HRW's investigations revealed systematic use of arbitrary arrest, torture of detainees, improper treatment of child prisoners and denial of access to lawyers.
"The Iraqi security forces obviously face tremendous challenges, including an insurgency that has targeted civilians," Ms Whitson said.
"We unequivocally condemn the insurgents' brutality. But international law is unambiguous on this point: no government can justify torture of detainees in the name of security."
The HRW report does not examine claims of mistreatment of prisoners by US or coalition forces.
US soldier Charles Graner was found guilty of abusing prisoners at Abu Ghraib earlier this month, while cases are also being brought against troops from the UK and Denmark.