The prime minister on Tuesday ordered an investigation into the conduct of Saddam Hussein's execution in a bid to learn who in the group of witnesses taunted the former Iraqi leader in the last minutes of his life then clandestinely released a video tape of his death to an Arab satellite television station.

The video captured by a cell phone camera contained audio of some witnesses taunting Saddam with chants of "Muqtada" and of the former leader responding that his tormentors were not being unmanly. It surfaced on Al-Jazeera television and the Internet late Saturday, the day Saddam was hanged shortly before dawn.

The taunts referred to Muqtada al-Sadr, the radical Shiite cleric who is a main backer of Prime Minister Nouri al-Maliki, the Shiite leader who pushed for a quick execution of Saddam.

Sami al-Askar, a close al-Maliki political adviser, told The Associated Press on Tuesday that the Iraqi leader had "ordered the formation of an investigative committee in the Interior Ministry to identify who chanted slogans inside the execution chamber and who filmed the execution and sent it to the media."

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The videotape was particularly inflammatory not only because the disrespectful chanting was clearly audible, but also for showing Saddam's actual death as he dropped through the gallows floor and then swung by his neck, his eyes open and his neck twisted dramatically to his right.

The clandestine video portrayed a much different scene than the official tape of the execution which was muted. It did not show the former leader dropping to his death.

Munqith al-Faroon, an Iraqi prosecutor whose job was to convict Saddam Hussein of genocide, was one of the small group of witnesses at the hanging and defended Saddam's right to die in peace.

He said he knew that "two top officials...had their mobile phones with them (at the execution). There were no mobile phones allowed at that time."

Saddam's execution and the way it was conducted have provoked anger among Sunni Muslims, who have taken to the streets in recent days in mainly peaceful demonstrations in Sunni enclaves across the country.

On Monday, a crowd of Sunni mourners in Samarra marched to a bomb-damaged Shiite shrine and were allowed by guards and police to enter the holy place carrying a mock coffin and photos of the former dictator.

The protest took place at the Golden Dome, a Shiite shrine bombed by Sunni extremists 10 months ago. That attack triggered the current cycle of retaliatory attacks between Sunni and Shiite Muslims, in the form of daily bombings, kidnappings and murders.

Meanwhile, the military on Tuesday announced the death of a U.S. soldier by a roadside bomb southwest of Baghdad. The blast Monday wounded three others, including an interpreter, as they talked with local residents about sectarian violence, the military said.

A roadside bomb also killed three Iraqi civilians and wounded seven others in eastern Baghdad on Tuesday, police said.

U.S. troops killed a suspected Al Qaeda weapons dealer and two other people in Baghdad raids Tuesday, and Iraqi forces detained more than 60 suspects over the past week, the U.S. military said.

Hundreds of demonstrators on Monday mourned Saddam in a Sunni neighborhood in northern Baghdad. Some praised the Baath Party, the outlawed nationalist group that under Saddam cemented Sunni Arab dominance of Iraq.

"The Baath party and Baathists still exist in Iraq, and nobody can marginalize it," said Samir al-Obaidi, 48, who attended a Saddam memorial in northern Baghdad.

In Dor, 77 miles north of Baghdad, hundreds more demonstrators march to a dedication of a giant mosaic of Saddam. Children carried toy guns and men fired real weapons into the air.

Mourners at a mosque in Saddam's hometown of Tikrit slaughtered sheep as a sacrifice. The mosque's walls were lined with condolence cards from tribes in southern Iraq and Jordan who were unable to travel to the memorial.

Sunnis were not only outraged by Saddam's hurried execution, just four days after an appeals court upheld his conviction and sentence. Many were also incensed by the unruly scene in the execution chamber.

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Many Sunnis are also upset that Saddam was put to death the day that Sunni celebrations began for Eid al-Adha, a major Muslim festival. The judge who first presided over the case that resulted in Saddam's death sentence said the former dictator's execution at the start of Eid was illegal according to Iraqi law, and contradicted Islamic custom.

The law states that "no verdict should implemented during the official holidays or religious festivals," said Judge Rizgar Mohammed Amin, a Kurd.

Rizgar presided over Saddam's trial on charges he killed 148 Shiite men and boys in Dujail, north of Baghdad, in a botched assassination attempt in 1982. The judge stepped down from the case after Shiite complaints that he was too lenient.

Monday's demonstrations came on a day that saw the U.S. military kill six Iraqis during a raid on the offices of a prominent Sunni political figure where American forces believed Al Qaeda fighters had taken refuge.

Iraqi authorities, meanwhile, reported Monday that 16,273 Iraqis — including 14,298 civilians, 1,348 police and 627 soldiers — died violent deaths in 2006. The total exceeds the Associated Press count by more than 2,500.

On the first day of the New Year, Iraqi police reported finding the 40 handcuffed, blindfolded and bullet-riddled bodies in Baghdad. A police official, who refused to be named out of security fears, said 15 of the bodies were discovered in the mainly industrial Sheik Omar district of northern Baghdad.

On Tuesday, police said the found 15 more bodies dumped in the north of the city.

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