A 4,000-man U.S. Marine regiment won a decisive battle Tuesday for control of this Baath Party stronghold without loss of American lives. After daylong fighting, the central Iraqi town was desolate and littered with charred vehicles and the bodies of Iraqi soldiers and civilians.

But yesterday key supply routes leading here from the south still weren't entirely secure, and the Marines' progress was slow.

The 1st Battalion, 4th Marines, based at Camp Pendleton, Calif., arrived outside the town Tuesday morning and immediately began taking fire from a nearby field. A three-hour firefight ensued amid reports that the foes were part of a Republican Guard division that had moved south from Al Kut, the next major town before Baghdad.

The Marines responded with rifle and mortar fire. Just before sunset, M1 Abrams tanks rolled in to reinforce the infantrymen. Soon after dark, an electrical storm lit the sky as Americans pelted the enemy with artillery from the 1st Battalion, 11th Marines, and .25 mm guns from the 2nd Light Armored Reconnaissance unit.

In the morning, the Iraqis fired small arms and two rocket-propelled grenades toward oil trucks near the Marines' command center. The Marines responded with howitzer fire, then rolled into As Shatra to mop up remaining enemy elements. They suffered no major injuries among the troops.

Iraqis suffered much more. The Marines found several families whose vehicles had been caught in the crossfire. At least two people in civilian clothing were dead at the scene; 12 apparent civilians were brought to the command center for aid and medical treatment.

Among the wounded were an elderly woman, a baby and a woman who died at the treatment site. A woman who appeared to be her mother stood over her body moaning and chanting prayers. The victims were to be airlifted to a military hospital for further treatment, but weather conditions prohibited evacuation. Instead, they were transferred to a combat support center.

Hassan Abed, a farmer from a nearby village, said most people had left before the Marines arrived.

When the Marines left, charred vehicles sat at the roadside, including a bus that held skeletal remains. The carnage included dead women and children and several men in the black pajama-style outfits of Iraqi paramilitary. The U.S. military had bound the wrists of some surviving men who were considered potential combatants.

The Marines were surprised by the amount of resistance they have encountered. Tom Parks, a gunner from Philadelphia who's with the 1st Battalion, 4th Marines, said this war has presented a greater challenge than what he encountered in the Gulf War.

I thought it would be quicker," said Parks. "It's like in Vietnam: "You can't understand their methods because they're so devoted to their cause."

For crew chief John Massey, an enlisted reservist from Florida, the fighting was not the worse part of the job.

"At that last checkpoint — I ran over a dead body," he said. The victim was wearing civilian clothes and appeared to have already been run over.

Later, the convoy came upon a burned-out bus surrounded by indistinguishable bodies. There was also a person in civilian clothes who may have been dead or alive and another in olive-drab clothing who was injured and pleading for mercy.

Nearby was a small boy about age 4 who appeared to have been blasted nearly in half but was trying to move. Marines radioed a request for a local ambulance service to be called to assist him.

The boy's plight moved the Marines.