"The fighting lasted from five to eight o'clock this morning (0100 to 0400 ," said Kamal, an electrician from the Yarmuk district on the road to the airport.

"It was hell. We were on a battlefield. It was on the airport road about 10 kilometres from the airport."

A US commander had earlier said a contingent of troops backed by tanks rolled into Baghdad on Saturday from the airport area they hold and came under fire.

"It started at first light," said Colonel Will Grimsley, commander of the First Brigade of the US army's 3rd Infantry Division.

Grimsley said elements of the division's Second Brigade had come under rifle fire and attack by rocket-propelled grenades (RPGs) as they entered the city. He did not give the size of the US force advancing.

He was speaking at Baghdad airport a day after US forces seized control of most of the facility in their 16-day-old drive northward to topple Saddam's regime.

CNN reported that US armour had penetrated the "heart of Baghdad" encountering occasionally stiff resistance from Iraqi forces using RPGs and horizontally fired anti-aircraft weapons.

SPACE.WIRE