Maj. Gen. William B. Caldwell also said that Saddam had been dignified and courteous to his American jailers to the moment when he was handed over to the Iraqis outside the execution chamber. The spokesman said no Americans were present for the hanging.

The leaked and unauthorized cell phone video, in which some of those present can be heard to taunt Saddam in the final moments of his life, set off an uproar both inside and outside Iraq.

Special coverage: Saddam Hussein Hanged Related readings:   Saddam buried in native village   Saddam compliant, calm in final moments   Bush: Execution will not halt violence  Americans cheer Saddam death   Iraqi-Americans pray for Saddam's death  Pentagon: US forces on high alert  Saddam still in US custody   US preparing for Saddam's execution  Saddam bids family farewell  Saddam lawyer seeks mercy  Iraq prepares for Saddam execution  Saddam says faces death without fear  Saddam calls for coexistence  Iraq court upholds Saddam's death penalty

The storm of criticism prompted the U.S. to publicly distance itself and Prime Minister Nouri al-Maliki to launch the investigation that led to Wednesday's detentions.

"In the past few hours, the government has arrested the person who videotaped Saddam's execution. He was an official who supervised the execution and now he is under investigation," said a key al-Maliki adviser, who spoke on condition of anonymity because he was not authorized to release the information.

Sami al-Askeri, a Shiite lawmaker who also advises al-Maliki, said two "Justice Ministry guards were being questioned. The investigation committee is interrogating the men. If it is found that any official was involved he will face legal measures."

Joining Caldwell in his criticism of the hanging, State Department spokesman Sean McCormack said U.S. officials had questioned conducting the execution on a Muslim festival day and as well as some procedures.

U.S. Embassy spokesman Lou Fintor said Ambassador Zalmay Khalilzad and his diplomatic team "did engage the government of Iraq on issues relating to procedures involved in the timing of the execution (of Saddam), given the upcoming holy days. While the government of Iraq gave consideration to U.S. concerns, all decisions made regarding the execution were Iraqi decisions based on their own considerations."

Also Wednesday, Iraqi and Arab media and a government official said preparations were under way to hang two of Saddam Hussein's co-defendants in the next few days, but the details still have to be worked out with the American military.

A Cabinet official, speaking anonymously because of the sensitivity of the information, said the two men would hang "at the beginning of next week."

Caldwell said those executions, like Saddam's, were the responsibility of the Iraqi government. "It's a sovereign nation. It's their system. They make those decisions."

Saddam's half brother Barzan Ibrahim, a former intelligence chief, and Awad Hamed al-Bandar, the former chief justice of the Revolutionary Court, were originally scheduled to hang with Saddam. But their execution was delayed until after Islam's Eid al-Adha holiday, which ended Wednesday for Iraq's majority Shiites.

In Washington, a lawyer for Bandar asked Supreme Court Chief Justice John Roberts to block the U.S. military from transferring custody of the condemned man to Iraqi authorities. U.S. courts have so far declined to intervene.

U.N.'s human rights chief Louise Arbour appealed to Iraqi President Jalal Talabani to prevent the execution of Ibrahim and al-Bandar, saying she was concerned with "the fairness and impartiality" of their trials.

As the hanging video swirled, Mowaffak al-Rubaie, the Iraqi national security adviser and a close ally of al-Maliki, hotly denied that he was involved in taking video of the execution. He spoke to CNN after the announcement of the arrest of the unnamed official in connection with the case.

The New York Times reported Wednesday, citing a prosecutor in the Saddam trial present at the execution, that al-Rubaie had recorded the execution with a cell phone.

Al-Rubaie said neither he nor any other Iraqi official had shot and leaked the video to Al-Jazeera television and Web sites. Instead, he suggested Sunni insurgents infiltrated the guard force and took the pictures.

According to the Times, Munqith al-Faroon, the prosecutor, told the newspaper "one of two men he had seen holding a cell phone camera aloft to make a video of Mr. Hussein's last moments up to and past the point where he fell through the trapdoor was Mowaffak al-Rubaie, Mr. Maliki's national security adviser."

But Al-Faroon, in an interview with The Associated Press, denied the report. "I am not accusing Mowaffak al-Rubaie, and I did not see him taking pictures," he said.

"But I saw two of the government officials who were...present during the execution taking all the video of the execution, using the lights that were there for the official taping of the execution," he added in a phone interview. "They used mobile phone cameras. I do not know their names, but I would remember their faces."

On its Web site, the Times later noted denials by al-Rubaie and al-Faroon.

As the storm over the handling of the execution gained strength, Caldwell was among several U.S. officials who suggested displeasure with the conduct of the execution.

"If you are asking me: 'Would we have done things differently?' Yes, we would have. But that's not our decision. That's the government of Iraq's decision," Caldwell said.

Saddam, Ibrahim and al-Bandar were sentenced to death for the 1982 killings of 148 Shiite Muslims in the town of Dujail, north of Baghdad, after a failed assassination plot against Saddam. They were convicted on Nov. 5, and the verdict was upheld by an appeals court on Dec. 26.

Saddam was hanged in Baghdad's Shiite neighborhood of Kazamiyah. During his regime, Saddam had numerous dissidents and opponents executed in the facility, located in a neighborhood that is home to the Iraqi capital's most important Shiite shrine ¡ª the Imam Kazim shrine.

As he faced his own death on the gallows, Caldwell said, Saddam "was courteous, as he always had been, to his U.S. military police guards."

The spokesman said Saddam's demeanor changed "at the prison facility when the Iraqi guards were assuming control of him, but he was still dignified toward us.

"He spoke very well to our military police, as he always had. And when getting off there at the prison site, he said farewell to his interpreter.

"He thanked the military police squad, the lieutenant, the squad leader, the medical doctor we had present, and the colonel that was on site."