A senior aide to former Iraqi President Saddam Hussein, General Amir al-Saadi, has surrendered to US forces in Baghdad.
Some Baghdad residents are trying to stop the looting
The general - Saddam Hussein's liaison with UN weapons inspectors in Iraq - is the first from a list of 55 high ranking officials wanted by the United States dead or alive to give himself up.
General al-Saadi told German television station ZDF, which filmed his surrender, that he did not know Saddam Hussein's whereabouts.
In Baghdad, meanwhile, US marines have begun patrols in another area of the city with no sign of an end to the disorder which has ravaged the capital for the past few days.
In other developments:
- US marines take the town of Kut in eastern Iraq, potentially opening up a new supply corridor to Baghdad from the south.
- Kurdish forces say they will withdraw from the city of Kirkuk in the oil-rich north by the end of Saturday, a day after it fell to Kurdish troops backed by US special forces
- US personnel begin to take control of the northern city of Mosul after telling Kurdish militia to stay on the outskirts of the city
- Coalition ground troops head for Tikrit after air strikes pounded the home town of Saddam Hussein
- In the southern city of Basra, UK forces are planning to start joint patrols with local policemen to try to stop looting there
ZDF said General al-Saadi decided to turn himself in after seeing on the BBC that he was being sought.
GENERAL AMIR AL-SAADI
Led negotiations with UN weapons inspectors
Depicted as the seven of diamonds on the US's "most wanted" pack of playing cards
The station said General al-Saadi insisted that Iraq did not possess weapons of mass destruction and he denied being a member of Saddam Hussein's former ruling Baath Party.
The general told the station he had spent the war in his Baghdad home and had decided to turn himself in because he felt "in no way guilty".
Television footage showed Mr al-Saadi bidding farewell to a woman before being driven away in the front seat of a US military jeep.
The BBC's Andrew North says a battalion of American marines has moved into the al-Quds district of north-east Baghdad, where they believe fighters still loyal to Saddam Hussein might be hiding.
Earlier, gunfire erupted around the Palestine Hotel in central Baghdad.
Correspondents say the shooting appeared to have been targeted at US troops - a sign that the city centre is still not secure.
In his weekly radio address on Saturday, US President George W Bush warned that "hard fighting" might still lie ahead for US forces trying to defeat remaining pockets of resistance.
US Central Command in Qatar has denied reports that US marines planned to impose a night-time curfew in Baghdad to try to put a stop to looting.
As looting spread to new areas of Baghdad on Saturday, the US said it planned to send 1,200 law enforcement officials to help Iraq set up a new police force.
Marines found gold-plated Kalashnikov rifles
Just 80 Iraqi police officers have answered America's call to return to their jobs.
In some affluent neighbourhoods, residents have formed vigilante gangs to beat off looters targeting their properties.
In an attempt to restore law and order, US marines have been interviewing public sector workers who want to return to their jobs, but it is uncertain if or when they would be paid.
Meanwhile, US troops searching a private residence in Baghdad on Saturday discovered a cache of weapons, including gold-plated Kalashnikov rifles bearing the inscription: "A gift from the president of the republic, Mr Saddam Hussein."
As gangs continued to plunder government offices and private property in Baghdad, the International Committee of the Red Cross (ICRC) said the city's medical system had all but collapsed.
ICRC spokesman Pascal Jansen said that out of the 32 hospitals in Baghdad, only three were partially operating.
At one city centre hospital, the BBC interviewed a doctor wearing a surgical mask and gown and carrying a Kalashnikov.
He said he had had to fight off looters, who were "coming like rats".
Red Cross officials said US troops had secured a hospital and a water treatment centre against looters - but that more work needed to be done to protect facilities.
An uneasy calm returned to Iraq's third largest city, Mosul, on Saturday, a day after Iraqi forces there gave up without a fight.
They don't even know what it's used for
A Baghdad doctor, who stood up to looters
The BBC's John Simpson, reporting from Mosul, says it is difficult to move around the city but things do appear to be stabilising.
Hundreds of American troops are reported to be patrolling the city centre after earlier coming under attack and being forced to withdraw to the nearby airport.
Reports from Mosul say 15 people have been killed and at least 200 injured during fighting between the Kurdish and Arab populations there.
Our correspondent says Kurdish leaders insist the violence involved only looters and criminals.
In nearby Kirkuk, US troops have been moving into the city to prevent any power vacuum, as Kurdish forces began to pull out on Saturday.
Turkey - nervous about Kurdish separatism - has demanded that the US take control and has sent monitors to satisfy itself that the Kurds are not establishing a power base there.