NAJAF, Iraq, Aug. 10 -- Bats flapped out of crypts, startling soldiers creeping through the cemetery with guns up. Graves opened beneath their combat boots. And an old enemy displayed a new professionalism, darting in clearly practiced moves between tombstone and mausoleum to stalk the Americans from above ground and below.
In the battle to control one of the world's largest graveyards, U.S. Marines and soldiers say they are coping with a lot, including lingering regret. The vast cemetery in Najaf is sacred to Shiite Muslims, perhaps 2 million of whom lie buried in miles of desert adjoining the shrine of Imam Ali, son-in-law of the prophet Muhammad.
Soldiers involved in the fighting described how many of the most recent graves are marked by photos, which crumble when U.S. forces shell the cemetery walls to reach the militiamen hiding within.
"Wives, daughters, husbands," said Sgt. Hector Guzman, 28, of the 1st Cavalry Division's 5th Regiment. "You just know you're destroying that tomb."
The Houston native shook his head. "It doesn't feel right sometimes."
"We feel bad that we're destroying, that we're desecrating graves and such," added Staff Sgt. Thomas Gentry, 29, of Altoona, Pa. "That's not what we want to do."
What the reinforced U.S. force in southern Iraq wants to do, commanders say, is destroy the Mahdi Army, the militia loyal to Moqtada Sadr, the militant Shiite cleric. The militia has bedeviled the U.S.-led occupation force in Iraq since October, when its largely impoverished, disaffected young gunmen first ambushed a U.S. patrol in a Baghdad slum. A far larger, sustained uprising in April and May undid much of the occupation's effort to establish security in Shiite-populated central and southern Iraq.
The current engagement, which began Thursday with another ambush, is billed by all sides as the final showdown.
Sadr this week brushed aside overtures from Iraq's interim government and vowed to fight to his last drop of blood. Iraqi officials, who consult closely with the U.S. commanders of the 160,000 foreign troops in Iraq, said the door was closed on negotiations.
To close observers, the final signal for decisive battle came with the departure of Grand Ayatollah Ali Sistani, the senior Shiite cleric in Iraq and a longtime opponent of Sadr, who is widely regarded as an upstart. Sistani, who is famous for not having left his Najaf house in six years, traveled to London last week, just as the fighting with Sadr's militia erupted. The official explanation -- treatment for a heart condition -- brings a smile to the lips of U.S. commanders here.
"A lot of people think it's the green light for us to do what we have to do," said Maj. David Holahan, executive officer of the 11th Marine Expeditionary Unit, which has responsibility for Najaf.
"The people will tell you they want it to end," said Army Lt. Col. Myles Miyamasu, a battalion commander in the 1st Cavalry Division's 5th Regiment, which hurried from Baghdad on Thursday to reinforce the Marines. "They're ready for this to be over."
On Tuesday, while senior commanders huddled to discuss an endgame, the cemetery once again doubled as a killing field.
While U.S. armored vehicles probed the huge brown expanse of graves and mausoleums, a small armada of warplanes, helicopters and armed drones circled overhead. When the vehicles drew fire, spotters located the attackers and radioed the coordinates to a crowded, vaguely air-conditioned room in a Marine operating base on the north side of Najaf.