The U.S. military says its troops are in full control of three key cities south of Baghdad: Najaf, Karbala, and Hillah, about 100 kilometers from the capital.

U.S. Army soldiers from the 101st Airborne Division began an offensive to root out the Fedayeen paramilitary fighters loyal to Saddam Hussein from Hillah.

The troops encountered resistance almost immediately on entering the city. About 200 Fedayeen fighters on pick-up trucks counter-attacked with machine guns and rocket-propelled grenades. Several Iraqi tanks also fired rounds at U.S. tanks.

U.S. forces responded with tank fire, artillery, and air strikes. Scores of Iraqi troops were killed during the four-hour battle. Three U.S. soldiers were wounded.

A lieutenant colonel with the 101st Airborne, Rick Carlson, says his soldiers, conducting a building-to-building search of the city, discovered what he called a "gigantic" warehouse full of weapons and ordnance.

Other weapons were found inside schools. He says the soldiers searched school buildings because that is where U.S. troops in neighboring cities of Najaf and Karbala have uncovered large weapons caches. "Every school that we have encountered in those three regions has been used as a weapons depot," he said. "So, whenever we have gone into a [militarily] built-up area, we go straight to a school."

The 101st Airborne Division has been charged with securing cities that had been overrun by the 3rd Infantry Division, which is now in Baghdad. Two other cities in the south, Najaf and Karbala, were secured earlier in the week. Lieutenant Colonel Carlson says Hillah is under U.S. military control.

Having all three cities under American control is vital to the U.S. Army because essentials, such as food, water and fuel, need to be trucked through the area to supply U.S. troops in Baghdad.

Now that the cities are secure, humanitarian assistance can begin. U.S. military commanders in the field say soldiers are already distributing food and clean water to Iraqi civilians in Najaf and Karbala. Hillah is expected to receive food and water by the end of the week.