The US-led coalition restored sovereignty to Iraq Monday, two days earlier than expected, as violence continued to rock the country and militants threatened to behead a captured US marine.
US overseer Paul Bremer handed over legal documents to Iraq's interim prime minister Iyad Allawi in a low-key ceremony to officially end 14 months of occupation since the ousting of Saddam Hussein.
Bremer also handed Allawi and the country's new President Sheikh Ghazi Al-Yawar a letter from US President George W. Bush, requesting a resumption of diplomatic relations between the countries that were frozen in 1990 after Saddam invaded Kuwait.
A coalition official said Bremer would be leaving Iraq later Monday.
The early handover pre-empted any plans by the coalition's foes to mark the expected transfer Wednesday, but it left the new Iraqi government to tackle a host of problems.
Allawi said Monday his administration would be taking a series of measures to try to restore security amid rampant unrest and an escalating foreign hostage crisis that has underscored Iraq's instability and overshadowed a NATO summit in Istanbul that was due to approve military training for the new authorities.
US marine captured
Militants earlier threatened to behead a presumed US marine they are holding captive unless Iraqi prisoners are released.
The coalition issued a statement Monday saying that a US marine operating west of the flashpoint town of Fallujah in western Iraq had been missing for the past week while another marine was killed in action on Saturday in the same area.
The coalition said it was unable to confirm whether the missing marine, identified as Corporal Wassef Ali Hassoun, of Lebanese descent, was being held hostage as reported by Arab television.
"Contrary to press reports... Naval Criminal Investigative Services cannot confirm that Corporal Wassef Ali Hassoun has been taken hostage," it said.
Arab news channel Al-Jazeera broadcast a tape on Sunday from a group calling itself the "Islamic Retaliation Movement - Armed Resistance Wing," which said it had abducted a marine and would execute him unless all detainees in US-led coalition prisons were freed.
It identified the US hostage as Hassoun, Wassef Ali, claiming to have abducted him after "infiltrating a US military base in Iraq," but gave no deadline for carrying out their grisly threat.
The tape showed a blindfolded moustached man, dressed in camouflage garb, with a sword brandished over his head and close-ups of identification cards.
In early April, a US soldier identified as Private Keith Maupin was captured by guerrillas and remains missing with no word on his fate.
Al-Jazeera had also broadcast video footage purported to be of Maupin.
Earlier Sunday, another Arab channel Al-Arabiya showed four hooded gunmen standing behind a man alleged to be a Pakistani who worked on a US base in Iraq threatening to behead him within 72 hours unless Iraqi prisoners are released.
The ID of the Pakistani was shown, naming him as Yussef Amjid, an employee of US contractor Kellogg Brown and Root.
The Pakistani government was unable to confirm whether one of its nationals had been abducted and no one at KBR was immediately available for comment.
The Tawhid wal Jihad, an Islamic militant group led by Jordanian Abu Mussab al-Zarqawi, said Saturday it would behead three Turkish hostages in 72 hours unless Ankara withdraws all its firms working for the US-led coalition in Iraq.
The threats came less than a week after the same group beheaded South Korean Kim Sun-Il after Seoul refused to cancel a planned deployment of 3,000 troops to northern Iraq.
On Sunday, 10 people were killed in violent incidents in and around Baghdad.
One American citizen identified by the coalition Monday as a US Defence Department civilian contractor was killed by gunfire as a coalition plane took off from Baghdad airport.
"While there was no significant damage to the aircraft, one person was wounded, which caused the aircraft to divert back to Baghdad International Airport for medical treatment. The individual later died of wounds," said the coalition's deputy director of operations, Brigadier General Mark Kimmitt.
Aircraft departing the airport have come under fire on three separate occasions in the past seven months.
Elsewhere, a US soldier died in a rocket strike on a coalition base in the capital at 3:00 pm (1100 GMT), the military said.
Two Iraqi children died and eight were wounded as two mortars landed near the Sheraton Hotel, which is popular with Western media and businessmen.
A group of youngsters were playing football when the mortar rounds burst, sending shrapnel flying, said Doctor Walid Hamid at the Al-Kindi hospital.
Six National Guardsmen were also killed in an attack on a checkpoint northeast of Baghdad, by gunmen armed with anti-tank rockets, police said.
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