AN ELITE group of native American trackers is joining the hunt for terrorists crossing Afghanistan’s borders.

The unit, the Shadow Wolves, was recruited from several tribes, including the Navajo, Sioux, Lakota and Apache. It is being sent to Tajikistan and Uzbekistan to pass on ancestral sign-reading skills to local border units.

In recent years, members of the Shadow Wolves have mainly tracked drug and people smugglers along the US border with Mexico.

But the Taliban’s resurgence in Afghanistan and the American military’s failure to hunt down Osama Bin Laden - still at large on his 50th birthday yesterday - has prompted the Pentagon to requisition them.

Robert M Gates, the US defence secretary, said last month: “If I were Osama Bin Laden, I’d keep looking over my shoulder.”

The Pentagon has been alarmed at the ease with which Taliban and Al-Qaeda fighters have been slipping in and out of Afghanistan. Defence officials are convinced their movements can be curtailed by the Shadow Wolves.

The unit has earned international respect for its tracking skills in the harsh Arizona desert.

It was founded in the early 1970s to curb the flow of marijuana into the US from Mexico and has since tracked people-smugglers across hundreds of square miles of the Tohono O’odham tribal reservation, southwest of Tucson.

Harold Thompson, a Navajo Indian, and Gary Ortega, from the Tohono reservation, are experts at “cutting sign”, the traditional Indian method of finding and following minute clues from a barren landscape. They can detect twigs snapped by passing humans or hair snagged on a branch and tell how long a sliver of food may have lain in the dirt.

Some military experts want the Shadow Wolves to help to track down Bin Laden. Despite a $25m bounty on his head and the use of billions of dollars worth of sophisticated equipment — including pilotless drones, electronic sensors, infrared cameras and satellite surveillance — US forces have so far failed to fulfil President Bush’s promise to capture Bin Laden “dead or alive”.

But a senior US official insisted last week that Bin Laden’s trail had “not gone stone cold”.

Vice-Admiral Mike McConnell, the new US director of national intelligence, told a Senate committee that Bin Laden and his lieutenant, Ayman al-Zawahiri, were setting up new training camps in northwestern Pakistan.

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