The United States military says its forces have secured Baghdad's international airport, after soldiers of the 3rd Infantry Division fought their way in overnight.
A US tank moves across part of the sprawling airport
A US spokesman said they had soundly defeated Iraqi resistance at the airport, including, he believed, elements from the Special Republican Guard.
But the BBC's Paul Wood in Baghdad says the battle for the airport may not be quite over - buses full of Iraqi soldiers were seen heading there on Friday morning.
And Iraq's Information Minister Mohammed Saeed al-Sahaf threatened a counter-attack on Friday night against coalition forces at the airport who, he said, were completely surrounded.
He told a Baghdad news conference Iraq might take "non-conventional" action - something which military analysts say is more likely to mean guerrilla action or suicide bombing, rather than a chemical or biological attack.
As people in the Iraqi capital remained largely without electricity and water after another night of sustained bombing, President Saddam Hussein went on TV to urge them to defend their city and vowed to defeat US-led forces.
In other military developments:
- US troops say they have found thousands of boxes containing vials of unidentified liquid and powder as well chemical warfare manuals at the Latifiyah industrial site south of Baghdad
- A car explosion at a US military checkpoint north-west of Baghdad kills three American soldiers, as well as the driver and a pregnant woman passenger
- US Central Command says it has received reports that about 2,500 Iraqi Republican Guards have surrendered to US marines between Baghdad and Kut, about 170 kilometres (105 miles) away
- Further south, British soldiers continue operations to secure the second city of Basra, establishing what they say is a holding position across the southernmost bridge into the city
Saddam International Airport now has a new name after being taken by US troops, US spokesman Brigadier General Vincent Brooks told a news conference at US Central Command in Qatar.
Baghdad International Airport, he said, was the "gateway to the future of Iraq."
The airport's capture prevented Iraq's leaders from
trying to flee by air and would enable coalition forces to use it now or in the future, he added
But General Brooks said it would take time to establish control over the Iraqi capital.
"We know there are forces inside that have intent to fight."
The attack on the airport began on Thursday evening with troops, backed by F-15E and F18 warplanes, moving in to seize the runway.
Night of hell
On the way to the airport, soldiers had to negotiate a single-lane road with Iraqi fighters firing
from all sides, the Associated Press reported.
Civilians trying to escape the fighting around the airport,
just 20 km (12 miles) southwest of the city centre, fled into
"It was a night of hell," one woman told Reuters. "There were planes all night dropping bombs and there was shelling all night."
At least 320 Iraqi soldiers were killed in the fighting, US military sources said. There were no reports of American casualties.
HAVE YOUR SAY
This battle will be won by America and its allies at a great cost to innocent Iraqi people
Mohammad Shoaib, New Delhi, India
The BBC's Gavin Hewitt, who is with the 3rd Infantry, says the Iraqi resistance has seemed fairly light and not particularly coordinated.
To the south-east of the capital, US marines are advancing on the Baghdad outskirts after pushing up the River Tigris from Kut overnight.
The BBC's David Willis, who is travelling with them, saw the burned out shells of Iraqi tanks and armoured vehicles lining the road.
Baghdad was plunged into darkness overnight by its first blackout of the war which cut in as the assault on the airport began .
Despite the call to arms by Saddam Hussein, there remain few defences in the capital, no real troop movements and a brittle air of business as usual, the BBC's Andrew Gilligan reports.
However, more families are packing their cars and leaving the city.
In other developments:
The foreign ministers of France, Germany and Russia have met in Paris to discuss the Iraqi crisis
- Iraqi Foreign Minister Naji Sabri responds to speculation about the health and whereabouts of Saddam Hussein, telling the BBC the president is alive and well
- The first convoy of UN emergency food aid - about 1,000 tons of wheat flour - crosses into northern Iraq from Turkey, headed for Dohuk.
- Red Cross lorries from Kuwait are carrying medical aid destined for Basra, while UN experts assess humanitarian needs in the southern town of Umm Qasr
The US Congress approves $80bn finance for war on Iraq but money earmarked for post-war reconstruction will not go to companies in France, Germany, Russia or Syria