A Canadian military spokesman, Lt. Luc Charron, said the four-day mission combed the region of Tora Bora, an area of caves, tunnels and underground bunkers with peaks as high as 10,000 feet.
Al Qaeda leader Osama bin Laden was believed to have fled Tora Bora in December during weeks of heavy bombing by U.S. aircraft, as pro-U.S. Afghan troops, aided by U.S. Special Forces and American airstrikes, closed in. But there was also speculation he might have been killed by the air strikes.
U.S. military spokesman Maj. Bryan Hilferty said forensics experts from the Army's criminal investigation department — similar to the Federal Bureau of Investigation — had accompanied the Canadians and collected several DNA samples from bodies found at the site.
But Hilferty said they were not searching for specific al Qaeda or Taliban leaders.
Reporting from Tora Bora, the Canadian Press news agency said that DNA samples were taken from 23 bodies unearthed from a cemetery in the Tora Bora region, and the Canadians thought they could have been some of bin Laden's body guards.
One prominently marked grave was initially thought to be possibly that of bin Laden but visual inspection of the body within showed that was not the case, said the news agency. The bodies were reburied in their graves afterward.
Military officials suggested finding and taking samples of the bodies had not been the main aim of the search of the region.
"Our mission was to conduct sensitive site exploitation and to destroy underground facilities in mountainous eastern Afghanistan, in order to deny access to al Qaeda access to the area," said Charron, a spokesman for 3rd battalion, Princess Patricia's Canadian Light Infantry. "The mission was a success."
About 400 Canadian troops, backed by Afghan infantry units, U.S. special forces and U.S. air support, participated in the mission, which began on Saturday.
Charron said no casualties had been reported and there had been no contact with al Qaeda or Taliban fighters. He said the Canadian troops had, "conducted a thorough exploitation, investigation and detonation of one major cave complex."
The cave entrance had been bombed, probably in December in by U.S. aircraft, and had to reopened, Charron said. It was sealed again after Canadian troops departed.
Waves of twin-rotor Chinooks escorted by Apache gunships returned the Canadians, laden with backpacks weighing over 100 pounds, to the air base at Bagram, an hour's drive north of the capital, Kabul.
The U.S.-led coalition has been stepping up its search for al Qaeda and Taliban fighters, exploring caves and bunkers they were suspected of having used in the recent past.
In the southeast, a 1,000-strong British-led force began a separate but similar operation last week.
Each of the missions falls under the umbrella of Operation Mountain Lion — the overall U.S-led search for Taliban and al Qaeda fighters in the eastern half of Afghanistan.
In another development, An Afghan warlord whose fighters rained hundreds of rockets on the eastern town of Gardez last month has been given a seven-day ultimatum to either surrender or face war, the provincial governor said on Tuesday. Paktia governor Taj Mohammad Wardak said renegade warlord Padshah Khan Zadran was a spent force grappling with mass desertions.
"The Gardez tribal council has issued a seven-day ultimatum from Tuesday to Khan telling him to either surrender or face war," Wardak said. "Most tribes who supported Padshah Khan are deserting him."