Iraq's oldest human rights group and the international Red Cross say they asked U.S. authorities last year to do something about alleged abuse of detainees at an Iraqi prison but got little response.

The U.S. military began an investigation at Abu Ghraib (search) in January, after an American guard informed commanders of abuses inflicted by colleagues. The probe has since widened into a look at whether there was systematic abuse at detention facilities in Iraq and Afghanistan.

The scandal mushroomed after pictures became public last week showing abuses at Abu Ghraib. Photos of smiling American guards stripping Iraqi prisoners and sexually humiliating them set off an international outcry and outraged Arabs.

President Bush apologized Thursday, saying he was "sorry for the humiliation suffered by the Iraqi prisoners and the humiliation suffered by their families." He said the images had made Americans "sick to their stomach."

Adel al-Allami (search), an official at the Iraqi human rights organization, said his group tried for months last year to get an audience with U.S. occupation officials.

He said it wanted to present a list of reported abuses at prisons as well as complaints about mistreatment of Iraqis during U.S. raids on homes in the search for insurgents.

"We knew of many human rights violations and sent a number of memos," al-Allami said, saying the group had reports of detainees being beaten and deprived of sleep.

Iraqi civilians also complain about heavy-handed methods used by soldiers during raids, including the hooding of detainees, damage to homes and theft of property, he said.

Also Thursday, Britain's Ministry of Defense said that it is questioning a soldier who has made new claims that British soldiers abused Iraqi prisoners. The soldier, who was not identified, had gone to British police with allegations of mistreatment.

Separate from the U.S. allegations, Britain is already investigating published photos allegedly showing its soldiers threatening and urinating on prisoners in Iraq.

The human rights organization, which was founded in 1960 but kept a low profile during Saddam Hussein's regime, asked repeatedly for meetings with coalition officials, but each time officials "would give excuses for not meeting," al-Allami said.

The group finally got a meeting three weeks ago and presented requests for compensation for mistreated Iraqis, he said.

"The treatment of these issues has not been positive at all," he said of U.S. administrators. "They have felt that Americans have total protection from any sort of prosecution ... This is the authority of the strong over the weak."

Red Cross (search) teams have been visiting Abu Ghraib every five or six weeks since last year, the organization's regional spokeswoman, Nada Doumani, told The Associated Press by telephone from Amman, Jordan.

"We were aware of what was going on, and based on our findings we have repeatedly requested the U.S. authorities to take corrective action," she said.

She said U.S. officials did make some changes, but added that they were not necessarily connected directly to "this issue about having naked people like this or like that, or homosexual practices."

She said Red Cross regulations prevented her from being specific about what practices the organization complained about or what corrections were taken.

The Army investigation at Abu Ghraib found that military police had on at least one occasion hidden prisoners during a visit by a Red Cross delegation.

A two-month-old report, disclosed last week, said the incident included six to eight prisoners and noted that "this maneuver was deceptive, contrary to Army Doctrine and in violation of international law."

Secretary of State Colin Powell telephoned the international Red Cross president, Jakob Kellenberger, on Thursday to assure him that the U.S. government was dealing with the reported abuse of Iraqi detainees.

"We will answer in a comprehensive way," Powell told reporters.

Six American guards have been charged and seven other officials have been disciplined for abuses investigated in January. But since then, evidence has grown that abuse was not an isolated occurrence.

The Army disclosed Tuesday that it was looking into 10 prisoner deaths and said two other deaths already had been ruled homicides. On Wednesday, an intelligence official said the CIA inspector general was examining two additional deaths involving agency interrogators.