A handful of the coalition troops sweeping through eastern Afghanistan have been knocked out of commission by the region's mountainous terrain, but none from contact with Al Qaeda or Taliban fighters, military officials said Sunday.

Three British soldiers were evacuated Saturday to Bagram air base from a mountain in the southeast of the country, Royal Marines spokesman Lt. Col. Paul Harradine said. Two of them were suffering from altitude sickness and the third had dysentery.

A Canadian soldier participating in a separate mission injured his knee Saturday and was also flown to the Bagram by helicopter, said Navy Lt. Luc Charron, a spokesman for the 3rd battalion, Princess Patricia's Canadian Light Infantry.

"It's very, very rough terrain over there," Charron said.

Several hundred Canadian soldiers, backed by U.S. air support and some Afghan infantry units, began Operation Torii on Saturday. Charron said it was aimed at gathering intelligence in an area where there had recently been "enemy activity."

The operation was the first major deployment of Canadian troops since April 17, when an American F-16 dropped a 500-pound bomb on Canadians conducting a live-fire training exercise near the southern city of Kandahar. Four Canadian soldiers were killed and eight others injured.

Charron said some "underground bunker facilities" had been searched and a half dozen new caves — seen by the coalition as potential enemy hide-outs — had been identified. One abandoned structure had turned up a rocket-launcher and some small arms ammunition.

The Canadians had planned to search another underground complex but it had been destroyed — apparently in the U.S. bombing campaign that ousted the Taliban late last year, he said.

Coalition troops have been stepping up their hunt for al-Qaida and Taliban fighters in the east, searching for documents, computer disks or anything that might give them new leads.

This week the British launched a new 1,000-man operation, called Snipe, in a part of southeast Afghanistan that had never been searched.

Harradine said British troops found "1,000 rounds of ammunition in a small niche in the rocks" Saturday, but soldiers had experienced no hostile fire.

He declined to say when the mission might be completed, saying only that "it's got a long way to go."

The Canadian- and British-led missions both fall under the umbrella of Operation Mountain Lion — the overall U.S.-led search for Taliban and al-Qaida remnants in the eastern half of Afghanistan.

In the north, meanwhile, representatives of two rival factions met in the wake of bitter fighting near the city of Mazar-e-Sharif last week that killed at least six people, local residents said.

The reported meeting between representatives of Gen. Atta Mohammed, military commander of four northern provinces, and Gen. Abdul Rashid Dostum, the deputy defense minister and interim Prime Minister Hamid Karzai's special representative to the north, comes amid signs of new tensions between the two sides.

Locals in Mazar-e-Sharif, the largest city in the north, said there were more armed men in the streets than in previous days and that the curfew had been moved up from 10 p.m to 5 p.m.