AT THE INTERNATIONAL AIRPORT, near Baghdad, April 5 - Lt. Col. Eric C. Schwartz did not see much of Baghdad this morning as his battalion of roughly 60 tanks, Bradleys and other armored vehicles churned along Highway 8, rumbling through first an industrial then a residential zone not far from the city's center.
All he recalled, when it was over, were the Iraqi soldiers, the artillery batteries, the trucks mounted with machine guns, the wisp and blast of rocket-propelled grenades, the whiz of bullets, the fiery explosions of cars packed, he assumed, with explosives.
"It was three hours of organized chaos," he said.
The colonel's battalion, part of the Army's Third Infantry Division, rolled into the heart of Baghdad in what, on the Iraqi side, must have seemed like the beginning of the invasion of the city itself.
The casualty count was unknowable, because the American soldiers moved virtually without stopping, but in the estimate of the Second Brigade's commander, Col. David Perkins, more than 1,000 Iraqi fighters died today.
For the soldiers - members of the Second Brigade's First Battalion, 64th Armored Regiment - it was a blistering gantlet of death and destruction that, they said, engulfed civilians as well as Iraqi fighters. It began just after dawn and ended when they arrived here at the airport, already occupied by the division's First Brigade.
A tank commander, sitting exposed in his open hatch, was killed when a grenade or mortar exploded in his face, soldiers and officers said. At least six American soldiers were wounded, some of them seriously.
One tank was destroyed, apparently by a rocket-propelled grenade, and had to be left behind in southern Baghdad after the crew was rescued. Other tanks and Bradleys were damaged, some pocked with the splash of rocket-propelled grenades and others charred by explosives.
A grenade hit Specialist Joseph A. Aiello's tank. "We were just riding along and all of a sudden you could hear a pow," he said. "The tank didn't really shake, but you could feel the vibration."
Sgt. Daniel R. Thompson, riding two tanks behind, saw the Iraqi who fired the grenade. He had fallen backward. "He had no legs," he said, but somehow managed to fire.
Specialist Aiello, a gunner, said he simply never stopped firing, despite the grenade's blast. The Iraqi fighters, he said, fired from streets, from groves of trees, from highway overpasses. Many mingled with civilians caught up in the unexpected armored thrust. Some people ran. Others waved white clothes or held up their hands.
"It was hard to shoot, because you don't want to shoot the civilians," he said. "It was hard to pick out the threat."
The four tanks of their platoon, part of Company A, bear the names of the four airliners that were hijacked on Sept. 11, 2001. Sgt. First Class Eric R. Olson said the men had stenciled them on the cannons as a way to motivate themselves, even though he was not sure there was a direct connection between that attack and the one this morning.
A family in a car stopped on Highway 8's median, evidently hoping to endure the sudden eruption of fighting they had driven into. A large truck, mounted with an antiaircraft gun, hurtled toward the column and was shot. It careered onto the median and struck the car, bursting into flames. As the American column passed, a man, a woman and three children - the youngest an infant - struggled with their injuries and burns. The man, presumably the father, was on his back. One child's fingers were virtually severed.
"Being a dad myself, that's the hardest part," said Sergeant Cassady, who manned a .50-caliber machine gun on the roof of an armored command vehicle. "I've got six kids at home, and I can't imagine it. I'd just as soon die than see that happen to my kids.