BAGRAM, Afghanistan -- Mopping up after the biggest U.S.-led offensive of the Afghan war, U.S. and Canadian troops killed three enemy fighters Thursday in a 90-minute gunbattle while clearing caves and bunkers in the mountains of eastern Afghanistan.
The Canadian Press news agency, which has a reporter with Canadian troops, said coalition troops subdued suspected al-Qaida or Taliban fighters with anti-tank weapons, grenades, heavy machine guns and small arms fire.
There were no U.S. or Canadian casualties, the agency said. The coalition casualty toll stood at eight U.S. special forces troops and three Afghan allied fighters.
All died in the first two days of the operation.
On Thursday, U.S., Canadian and Afghan troops combed the area around the Shah-e-Kot valley for intelligence information and any stray enemy fighters left behind after al-Qaida and its Afghan Taliban allies fled the area following Operation Anaconda's 12 days of airstrikes and ground fighting.
Maj. Gen. Frank L. Hagenbeck, commander of coalition troops in Afghanistan, told reporters he had ordered DNA tests on remains of al-Qaida fighters to determine whether any senior figures in the terrorist network were among the dead.
Neither Osama bin Laden nor Taliban leader Mullah Mohammed Omar was believed to be in the area on March 2 when U.S. forces and their Afghan allies launched the offensive.
Hagenbeck said some of the 20 prisoners captured in the operation indicated that "second and third tier" al-Qaida leaders had been killed and he ordered the tests to make sure that no senior figures were there too.
"Even if it's a long shot that maybe one of these al-Qaida leaders (was there), we want to go through every means we've got available to us to try to positively identify them," Hagenbeck said.
He has said coalition forces searching the caves had already found bomb-making devices, extensive weapons caches, manuals on how to attack individuals in cars and blow up bridges.
He also said the cave searches have turned up large weapons caches, some of which will be turned over to the Afghan army.
Hagenbeck also acknowledged that some civilians were killed in the fighting, though he did not say how many. He blamed the deaths on the al-Qaida fighters, who set up mortar positions between the houses in the hamlets of the Shah-e-Kot Valley.
"It's always tragic when noncombatants are killed in something like this," Hagenbeck said.
It is still uncertain how many enemy fighters were killed in the operation. Some U.S. officer have estimated as many as 500 al-Qaida fighters were killed, but Afghan fighters said only 25 bodies had been found in the initial sweep of the area. Others may be buried in caves that collapsed during the bombing.
U.S. and Afghan officials are also uncertain how many fighters may have escaped and are trying to flee to Pakistan. U.S. attack helicopters patrolled over the area Thursday trying to locate any pockets of al-Qaida survivors.
Pentagon spokeswoman Victoria Clarke said Wednesday that fighting in the Shah-e-Kot area had "mostly ended" and that troops were in the "exploitation phase," going cave to cave in search of bodies, weapons and intelligence information.
"We still have a long way to go in Afghanistan," she warned. U.S. and Afghan officials believe there are still pockets of al-Qaida and Taliban fugitives in several southern and central provinces, as well as in Pakistan.
In Berlin, the leader of Afghanistan's interim government, Hamid Karzai, said Thursday that he believes Taliban and al-Qaida fighters still pose a threat to his country's stability.
"There's no doubt there will be isolated pockets of terrorism elsewhere in the country," Karzai said.
U.S. officials had hoped to prevent a repeat of the flight from Tora Bora, the cave complex U.S. troops hammered for weeks in December on suspicion that bin Laden was inside.
Afghan militias from the area conducted most of the ground fighting at Tora Bora, and U.S. authorities said they apparently let many al-Qaida fighters escape to Pakistan. When Tora Bora was finally overrun, there was no sign of bin Laden.