BAGHDAD -- The Iraqi government launched an investigation yesterday into the apparent torture of detainees in a secret Interior Ministry jail after the US military found 173 prisoners inside who appeared to have been abused, Prime Minister Ibrahim al-Jaafari said.
It was the first time that the country's US-backed government installed in April had acknowledged the possible abuse of prisoners at one of its facilities. The detainees appeared to have been mostly Sunni Arabs, a group that has long contended that Shi'ite Muslim militias close to the political parties that dominate Iraq's ruling coalition are carrying out a shadowy campaign of vendettas against perceived political and sectarian foes.
The discovery Sunday of the makeshift prison, with prisoners held in murky circumstances, lent credibility to those charges. The new scandal also threatened to exacerbate sectarian rifts at a time when the US military and Iraqi government had been taking steps to mend them.
Soldiers of the US Army's Third Infantry Division and Iraqi troops found the prisoners when, acting on a tip and searching for a missing teenager, they demanded to enter the bunker-like building hidden away in a quiet, well-to-do neighborhood near Baghdad University.
The injuries were significant enough that medical care was summoned to the site. The deputy interior minister, Major General Hussein Kamal, said some of the prisoners had been paralyzed by the beatings they had received, and in some cases their skin had been peeled off by abusers. Jaafari said there were apparent ''torture marks" on some detainees.
Journalists have not been given access to the prisoners, who have since been moved to another, more suitable location, according to the government.
Facing parliamentary election next month, Jaafari's Shi'ite-led government appeared to want to move quickly to mitigate the impact of the reported abuse and address the question of whether other such sites exist.
The US Embassy and multinational forces congratulated Jaafari for his quick promise to investigate. Ambassador Zalmay Khalilzad and General George Casey, the two ranking US officials in Iraq, have discussed the condition of the detainees in the Interior Ministry jail with Iraq's leaders ''at the highest level," a joint statement said.
The statement called the mistreatment of detainees ''totally unacceptable" and said that the US government, including officials from the FBI and Department of Justice, would give technical help ''to investigate, prosecute and bring to justice" anyone responsible.
Amnesty International, responding to the report, said it welcomed the government's investigation and asked that it be expanded to include all allegations of torture in Iraq.
Standing outside the facility in the Jadiriya neighborhood last night, Kamal blamed the alleged prisoner abuse on inexperienced and untrained officers who were brought into the police force during the chaotic days following the ouster of former president Saddam Hussein.
The low-slung building, which appeared from the outside to have been constructed as a bomb shelter during the Iran-Iraq war from 1980 to 1988, covers about an acre of southern Baghdad. It is hidden from the main road behind houses and apartment buildings and surrounded by garbage-strewn earthen berms.
''We have pictures and evidence of the prisoners that were harmed, and every Iraqi citizen has the right to punish those who mistreated those prisoners," Kamal said. ''Those cases have been handed over to the Iraqi court to decide."
Kamal, who is the ministry's undersecretary for security, said that prisoners should never have been taken to such a facility.
''This place is not suitable for holding people. It was a shelter," he said. There were no cells, and people were held in ordinary rooms, he said.
It was not clear why the prisoners had been arrested in the first place. Most detainees are suspected of supporting the Sunni Arab insurgency.
Saleh al-Mutlaq, a Sunni politician, said that torture is widespread in Interior Ministry detention centers and that the force has been infiltrated by the Badr Brigade, the military wing of Iraq's largest Shi'ite party.
''Some Iraqis are having their heads opened with drills, then their bodies are thrown in the streets," Mutlaq said. ''This shows that the United States should stop these acts since it is the force that occupies Iraq."
Ahmed al-Barak, a human rights lawyer working for the government, blames the legacy of the former regime for the abuses. Unlike the Iraqi Army, which was disbanded after the Ba'athist government collapsed and is now being rebuilt from scratch, many Iraqi police are holdovers from the old regime.
''The idea of human rights is a new issue for Iraqi society," he said. ''The majority of Iraqis were raised in a culture of violence, and I think we need time to make people understand that there's another way."
The allegations follow the Abu Ghraib prisoner abuse scandal last year, in which US troops were found to have physically abused and sexually humiliated detainees at a notorious prison on the western outskirts of Baghdad. At least eight low-ranking US soldiers have so far been court-martialed for their part in the abuse, which angered Iraqis and fueled the two-year-old insurgency.
Also yesterday, the US Army said it was looking into whether US forces in Iraq put prisoners in a cage with lions in 2003, but Defense Secretary Donald H. Rumsfeld called the accusation by two Iraqi men ''far-fetched."
Two Iraqi businessmen, Sherzad Khalid and Thahe Sabbar, made the allegation as part of a lawsuit against Rumsfeld and top US military commanders in Iraq filed by two rights groups, the American Civil Liberties Union and Human Rights First.
The men contend US jailers took them to a cage containing lions on the grounds of a presidential palace in Baghdad during an interrogation seeking some sort of a confession, forced them into the cage entrance, then pulled them back and shut the cage door when the lions approached.
Material from the Chicago Tribune and Associated Press was included in this report.