In the northern desert hometown of Saddam Hussein, die-hard Iraqi loyalists are hunkering down under withering U.S. airstrikes and digging in for a potential last stand.

The dusty town of Tikrit has been branded a regime stronghold by the U.S. military. Its sprawling presidential complexes and the tunnels beneath them could serve as Saddam's final hideout. And the city's blood-bonded tribesmen could carry on fighting even if their leader is dead.

U.S. Brig. Gen. Vincent Brooks suggested Wednesday that Iraqi reinforcements -- pressured from the north by U.S. and Kurdish fighters and from the south by the fall of Baghdad -- were converging on Tikrit, 100 miles north of Baghdad.

"We certainly are focused on Tikrit to prevent the regime from being able to use it as a place to command and control, to restore command and control, or to hide," he said.

Ten or more Iraqi army divisions -- as many as 80,000 troops -- were in the area between the capital and the Kurdish-controlled areas of far northern Iraq, Joint Chiefs of Staff Chairman Gen. Richard Myers said Wednesday.

Whether those Iraqis were willing or able to put up much of a fight was unclear, however. Pentagon officials said Iraqi military lines of communication were severed and they saw no evidence Iraqi forces were getting any direction from above or working in any coordinated manner.

U.S. officials said special forces troops are already there, "softening the battlefield" before any U.S. ground troops move in. Also, coalition aircraft are hitting hard at the Republican Guard's Adnan division there. The Navy said its warplanes bombed a barracks and garrison.

American troops have also blocked the roads into Tikrit from Baghdad to stop Iraqi leaders from fleeing there and troops from regrouping.

Resistance could be fierce in Tikrit if ground coalition ground troops ever move in.

Saddam built loyalty by showering largess that turned the Tigris River backwater into a sprawling city of 260,000 after his Baath Party assumed power in 1968. Saddam's birthplace hosts an air base and air force academy in addition to the Republican Guard garrison.

Tikrit's martial pride predates Saddam; the city was the birthplace of the Kurdish warrior Saladin, who defeated the Crusaders during the Middle Ages.

Today, Tikrit is a power center for Sunni Arab tribes, and they may hold out for as long as possible out of fear of losing power to the nation's Shiite majority.

Their fears could only be stoked by scenes of jubilant Shiites celebrating Wednesday in downtown Baghdad. The Shiites were brutally oppressed by Saddam's Sunni regime and see the U.S. forces as liberators.

If Saddam goes into hiding in Tikrit, he may be able to organize clandestine cells and launch a guerrilla war against U.S. troops.

The Iraqi fighters in the area are probably a combination of military, irregular forces and Baath Party loyalists, Brooks said. He would not say when he thought coalition ground forces would move in, saying only, "There is still work to be done."

"This battle definitely isn't over," said Navy Capt. Frank Thorp, a spokesman at U.S. Central Command. "We know there are very strong possibilities of tougher fights to follow."