Baghdad is in the grip of civil disorder as US troops who seized control of the city centre two days ago struggle to contain the violence.
The looters carry off absolutely everything they can
As jubilation gave way to lawlessness, fires raged out of control on Friday in government and commercial buildings, while looters raided shops, museums, homes and even hospitals.
Doctors and nurses at the al-Kindi hospital - already ravaged by looters - have taken up arms to protect themselves.
The American forces in Baghdad say they are taking measures to curb the chaos - setting up an operations centre at the Palestine Hotel, in the city centre, and calling on professional people to come forward to help run public services.
But BBC correspondents in the city say the presence of US troops does little to deter the armed mobs. And in any case the troops are too thinly-spread, concentrating on guarding government buildings and searching for weapons caches.
There was intense gunfire in north-east Baghdad in the mainly Shia suburb of Saddam City, and a US marine position came under fire there. It is thought that local residents may be involved in clashes with people still loyal to the regime of Saddam Hussein, says the BBC's Gavin Hewitt.
The scenes in Baghdad have been replicated in the northern city of Mosul, where widespread looting broke out after the Iraqi army abandoned the city to US-backed Kurdish fighters.
Like Kirkuk just 24-hours before, Mosul fell without a fight.
In other developments:
- A senior Kurdish official says Kurdish militia have begun withdrawing from Kirkuk, but the BBC's Dumeetha Luthra says there is little evidence of change on the ground.
- US President George W Bush says the war will be over when "commanders on the field tell me the objective has been achieved".
- Russian President Vladimir Putin says under no circumstances should a new colonialism be allowed to establish itself in Iraq. Speaking at a summit in St Petersburg with the leaders of France and Germany, he says Iraq's fate must be in the hands of the Iraqi people.
- US special forces are involved in fierce fighting with Iraqi forces near the town of Qaim, close to the border with Syria, at a site suspected of harbouring missiles or even weapons of mass destruction.
- Two Iraqi children are killed and nine other civilians injured after US marines open fire on a vehicle approaching a checkpoint at speed in the southern town of Nasiriya
US Secretary of State Donald Rumsfeld has denied Iraq was falling into chaos, describing the scenes of looting as "untidy".
"Free people are free to make mistakes and commit crimes and do bad things," he told reporters.
"I don't think there is anyone in those pictures or any human being who does not prefer to be free and recognise that you have passed through a transition period like this and accept it as part of the price of getting from a repressed regime to freedom."
Medics take up arms
The International Committee of the Red Cross says it is profoundly alarmed by the situation in Baghdad, which it says is verging on anarchy. It has appealed to US-led forces to restore order urgently.
The organisation, reminding the US and Britain of their legal responsibility to protect civilians and essential services, says two days of looting has left Baghdad with virtually no functioning hospitals.
Even the presence of US troops on the street does little to deter them
The BBC's Caroline Hawley says at one hospital in Saddam City, armed civilian volunteers are stationed outside.
The BBC's Paul Wood, also in Baghdad, says much of what is stolen is of little or no use to those who take it.
Vital hospital equipment such as heart monitors and incubators have been stolen and even the laboratories ransacked - centrifuges and microscopes smashed.
Our correspondent says he saw a gang of looters carrying off an assortment of shiny metal instruments and bottles of chemicals.
"They don't even know what it's used for," said the doctor of veterinary medicine who accompanied him.
Stripped of equipment Baghdad hospitals still treat the injured
In this instance the doctor followed the looters to their truck and chastised them, shaming them into returning the equipment - one brave man against a mob - but our correspondent says this is not usually the case.
United Nations aid agencies say the humanitarian situation is worsening and the disorder in Iraq means it is not safe for them to send their workers in to help civilians.
The country's cultural heritage is under threat too. AFP news agency says part of Iraq's largest archaeological museum has been looted, and ancient artefacts destroyed and stolen.
The BBC's David Willis in Baghdad says a small minority of the population is carrying out the looting and most residents are hunkered down behind locked doors in fear.
However, he says that the spirit pervading the streets is a sense that "the Iraqi regime had stolen from the people for years and now they are taking it back".
HUMAN COST OF WAR
US: 99 dead (including 26 in non-combat accidents, 5 to 'friendly fire', 2 under investigation), 8 missing
UK: 30 dead (including 16 in non-combat accidents, 5 to 'friendly fire')
Iraq: At least 1252 civilian deaths*, military deaths unknown
*Former regime figures, 3 April
General Jay Garner, the former US general in charge of overseeing the creation of a new government in Iraq, says his first priority will be to set up a new police force.
Under new rules of conduct issued on Friday by General Tommy Franks, American troops have been forbidden from using deadly force to prevent looting.
Some Baghdad citizens are taking the law into their own hands - at one hospital which was plundered, the BBC's Andrew North said he saw one boy, allegedly a looter, beaten to death in front of him by residents.