The prime minister of Iraq has launched an investigation to learn who leaked a video of Saddam Hussein's hanging and who taunted him moments before his death.

The investigation will be conducted by a committee of the Interior Ministry, Sami al-Askari, an advisor to Prime Minister Nouri al-Maliki, told the Associated Press.

This video image, released by Iraqi state television, shows Saddam Hussein's guards wearing ski masks and placing a noose around the deposed leader's neck moments before his execution Saturday.
(Associated Press)

The video, believed to be filmed on a witness's cellphone during Saturday's execution, was circulated widely on the internet and was broadcast by Al-Jazeera television.

On it, witnesses can be heard shouting insults at Saddam moments before the gallows trap door opens and the deposed Iraqi leader plummets to his death.

Many witnesses chant slogans from radical Shia cleric Muqtada al-Sadr, a major backer of al-Maliki.

Saddam is heard shouting angry retorts at those insulting him.

The video, though grainy, is graphic. Saddam can be seen swinging by his neck, his eyes open and his neck twisted to the right.

He was in the middle of saying a prayer when the trap door opened and he dropped.

Munqith al-Faroon, an Iraqi prosecutor who helped convict Saddam of genocide, was one of the small number of witnesses at the hanging.

He said two top officials had their cellphones with them at the execution, although other witnesses had their phones taken away beforehand.

"I am certain that the chanting at the moment of the execution was not organized, and that those chanting were not being ordered to do so," al-Faroon said.

"The guards made a decision to do so by themselves. This is the truth. I shouted at them and ordered them to keep silent, my voice is very clear in the recording."

Cellphones taken from witnesses

Al-Maliki adviser Sadiq al-Rikabi said cellphones were taken from witnesses before they boarded a helicopter to the execution site.

"I am full of hope that the results of the investigation will be announced, and the person who did this act should pay a price," he told U.S.-financed Al-Hurra television.

In the leaked video, Saddam is heard responding to the taunts.

"Is this manly?" he asks at one point.

A voice responds, "To hell."

Another voice calls out, "Long live Mohammed Baqir al-Sadr," a reference to the Dawa party founder and Shia cleric who was executed by Saddam in 1980.

'Please no, this man is being executed'

Then, a voice, purportedly that of al-Faroon, says: "Please no, this man is being executed, please no, I beg you, no."

The leaked video differs from the official video released hours after the execution. That tape was muted and did not show the moment of Saddam's death.

The CBC, along with several other news organizations, chose not to broadcast the leaked video in its entirety.

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

On Monday, a crowd marched to a bomb-damaged Shia shrine and were allowed by guards and police to enter, carrying a mock coffin and photos of Saddam.

Meanwhile, the U.S. military announced the death of a U.S. soldier by a roadside bomb southwest of Baghdad. The blast Monday wounded three others.

With files from The Associated Press