The commander of American ground forces in Iraq, Lt. Gen. David D. McKiernan, has asked the Pentagon to fly in part of an armored cavalry regiment from the states, about 700 soldiers, to help protect the supply lines in southern Iraq which have come under unexpectedly fierce attack from Saddam's so-called Fedayeen fighters, CBS News Correspondent David Martin reports.
The 2nd Armored Cavalry Regiment from Fort Polk, La., and the 3rd Armored Cavalry Regiment from Fort Carson, Colo., will be deployed.
In Washington, Defense Secretary Donald Rumsfeld said the increase of the force size in Iraq was pre-planned and has nothing to do with how the war is going.
"We are increasing the number of forces in the country every day," Rumsfeld said.
The news of reinforcements comes as 1,000 U.S. paratroopers from the 173rd Airborne landed in northern Iraq and seized an airfield, and the Army's 3rd Infantry pulled within 50 miles of Baghdad.
In other major developments:
Lt. Col. Thomas Collins, spokesman for the U.S. Army Southern European Task Force, confirmed Wednesday that a unit of the 173rd Airborne, based in Vicenza, Italy, arrived in northern Iraq on Wednesday night.
"Approximately 1,000 troops went in. Really, I can only tell you, 'Yes, they've gone in. They're on the ground,'" he said.
It was the first major movement by U.S. troops to open a northern front that initially was supposed to involve troops moving through Turkey. The northern part of Iraq is dominated by Kurds, but there are substantial Iraqi forces just over the border of what had been the no-fly zone.
As U.S. troops landed in the north, Saddam Hussein's forces were shifting their attention south.
Firefights broke out all along the supply lines connecting the rear areas to the frontlines where the Army and the Marines are moving into position to do battle with the Republican Guards on the southern approaches to Baghdad. The Iraqis driving pickups and SUVs and firing rifles and grenade launchers spring ambushes and flanking attacks but are badly outgunned.
"In the middle of bad conditions our forces responded by destroying more than 30 enemy vehicles and killing enemy personnel in the hundreds," said Pentagon spokesman Maj. Gen. Stanley A. McChrystal.
Despite the lopsided outcomes, the Iraqis have turned the routes, which fuel and ammo trucks use to carry supplies forward, into ambush alleys.
Combined with the blowing sands, the attacks are complicating the drive toward Baghdad as units have to stop and wait for their fuel supplies to catch up with them.
But for the record, the Pentagon insists there's no delay in the battle plan.
"It has not thrown the force off its plan," said McChrystal. "The logistics have flowed, continued to flow smoothly, additional forces continue to push forward. The plan has moved almost exactly with expectation."
For the second straight day, swirling sandstorms hampered American units. The bombing campaign was crimped, as well, but Baghdad television was knocked off the air for several hours, and explosions were heard, as well, near the oil-rich city of Kirkuk in the north.
President Bush traveled to U.S. Central Command in Florida and offered thousands of cheering troops and their families an upbeat, but guarded assessment of the war.
"Our military is making good progress in Iraq," said the president, "yet this war is far from over."
CBS News Correspondent Bill Plante reports Mr. Bush's speech as originally written said, "Our progress is ahead of schedule," but with troops experiencing unexpected resistance in Iraq , Mr. Bush changed that to "good progress."
In London, Amnesty International said both sides may have committed war crimes, including coalition missile attacks on Iraqi TV. The human rights group accused Iraqi forces of deliberately shelling civilians in Basra and placing military objectives close to civilians.
British military sources said an Iraqi column of about 120 vehicles was headed southeast out of Basra, apparently using the sandstorm to try to escape undetected.
British forces have ringed Basra, Iraq's second city, for the past several days, exchanging artillery fire with forces loyal to Iraqi leader Saddam Hussein. The British said they were coming to the defense of inhabitants who rose up against the regime on Tuesday.
"Truthfully, the reports are confused, but we believe there was some limited form of uprising," Prime Minister Tony Blair told Parliament on Wednesday. "Once people know that Saddam's grip on power is being weakened, then there is no doubt at all that they wish to opt for freedom rather than repression."
Iraqi officials have denied there was any uprising Tuesday in Basra.
Basra's trapped civilian population of 1.3 million is believed to be fast running out of food and in danger of outbreaks of disease from contaminated water.