An Iraqi policeman watches a large-screen broadcast of the official video showing Iraqi President Saddam Hussein moments before his execution

Iraqi officials say they have launched an inquiry into the conduct of the execution of Saddam Hussein and how it was secretly recorded.

Unlike the official execution videotape, which was silent, a mobile phone camera captured picture and sound of Saddam being taunted and then dropping to his death. One person also can be heard shouting "Moqtada," the name of a radical Shi'ite cleric and opponent of Saddam.

In recent days Saddam supporters have marched in several Iraqi cities and in Jordan, citing the unauthorized video as evidence the execution was a sectarian killing.

Meanwhile, Iraqi officials said they found at least 15 bodies across Baghdad Tuesday. All are believed to be victims of sectarian death squads.

Also in Baghdad, the U.S. military says coalition troops killed three terrorists, including an al-Qaida weapons dealer, in a morning raid. Iraqi security officials say a bomb blast killed three people and wounded seven others in the capital city.

In Fallujah, a U.S. military statement Tuesday says an Iraqi soldier was fatally wounded during an incident with an American Marine at a guard post in the Fallujah Government Center on December 30.  The military says it has launched a criminal investigation, and the Marine has been assigned to administrative duties. 

In a separate statement, the U.S. military says that during the past week, Iraqi forces have detained more than 60 people in raids between the cities of Ramadi and Fallujah.

Meanwhile, a Sunni politician, Saleh al-Mutlah, told Al-Arabiya television that U.S. aircraft bombed his offices and a nearby home Monday, killing a family of four and two workers from his political party, The National Dialogue Front.

But the U.S. military says the six were suspected terrorists and that they were killed during a raid on a suspected al-Qaida safe house in Baghdad.

Some information for this report was provided by AFP, AP and Reuters.