US forces are tightening their grip on central Baghdad, advancing street by street and blitzing targets with planes and tanks as Iraqi defenders fight an apparently hopeless battle with anti-tank weapons and rifles.
Consolidating the stranglehold on the city of 5 million people, US Marines captured the Rashid air base in the southeast, three miles from the centre.
The military said it did not know whether an air strike on a building in a wealthy district of Baghdad yesterday had killed Iraqi President Saddam Hussein, but added his grasp on the nation of 26 million was fast disintegrating.
"We are sitting in the centre of the city with almost an armor brigade right now, which is extraordinary," Maj Gen Stanley McChrystal told a Pentagon briefing.
"The end game is the end of the regime, and that's much closer than people thought it was," added Maj Gen McChrystal, vice director for operations on the US military's Joint Staff.
He said the US had no "hard battle damage assessment" on who was killed in the airstrike on a residential district aimed at Saddam, but called it very effective.
Aircraft, tanks and artillery pounded the nerve center of Saddam's administration in a thundering raid in central Baghdad that began at dawn, meeting only scattered Iraqi resistance in what appeared to be the final battle for Saddam's capital.
While Marines move to link up with forces from the 3rd Infantry Division, currently in north Baghdad to the west of the Tigris river, troops have been warned that Saddam's elite guard still posed a threat.
"The Special Republican Guard we believe still exists, we believe it is still operating inside Baghdad, we believe that it has great potential for some sharp fights," Maj Gen McChrystal said.
US special forces in the north of Iraq are preventing Iraqi troops moving south toward Tikrit, Saddam's birthplace, or toward Baghdad, and air strikes are continuing on Iraqi military forces in the north.
Iraq's information minister says Iraqi forces will "tackle and destroy" the invaders. "They are going to surrender or be burned in their tanks," Mr Mohammed Saeed al-Sahaf told reporters.