Gates visited a small, remote outpost 48 km north of Kandahar, where the Fort Lewis, Washington-based Stryker unit has lost 22 men and suffered an additional 62 wounded since arriving here last summer.

The latest injuries came Monday night, and the latest death three days ago.

Gates praised the 800-soldier unit and told the troops that as the fight shifts toward securing Kandahar itself later this year, they will again be “at the top of the spear.” Gates flew to Kandahar early Tuesday for meetings with US and British generals overseeing the current military campaign in Marjah. He presented Silver Stars for valor to two Army aviators before his visits with US forces at bases elsewhere in the south.

On Monday, the Pentagon chief said the progress made in the Marjah offensive, launched last month, is encouraging, but he stopped short of saying the war is at a turning point. The Marjah campaign routed most Taleban fighters from a town they once controlled, without a high casualty toll for US troops and the Afghan security forces fighting alongside them.

“People still need to understand there is some very hard fighting, very hard days ahead,” Gates told reporters.

Gates met Monday in Kabul with Gen. Stanley McChrystal, the top US and NATO commander in Afghanistan. McChrystal said preparations have begun for a crucial campaign to assert Afghan government control over Kandahar, spiritual home of the Taleban.

Gates traveled to Afghanistan to check on the progress of the war's expansion, directed late last year by President Barack Obama.

The 30,000 additional US forces Obama ordered are now arriving and most will be in place by summer. Without being specific, McChrystal suggested that any heavy fighting in Kandahar will wait until more US and NATO troops are ready.