SAS on the ground since January

Targets being pursued by coalition forces in Afghanistan will have been pinpointed in covert operations by the SAS.

Experts believe soldiers will have been on the ground in eastern Afghanistan since January, working in small teams to establish the points of al Qaeda's operation.

They will have supplied the information that, following the rout of the Taliban by coalition forces, al Qaeda appears to have successfully re-built itself, primarily by regrouping across the border in Pakistan.

Analysts say the SAS will probably have two of its three squadrons in the combat zone. They will have co-opted specialists from the Paratroop Regiment and the Marines.

During Operation Jacana and specifically Operation Ptarmigan - the name given to this particular part of the coalition effort - the SAS will be providing Brigadier Roger Lane, the Royal Marines' commander, with detailed "real time" intelligence.

Senior officers will be deployed to relay that information to him through SAS headquarters at Hereford, or the Permanent Joint Headquarters at Northwood in Middlesex.

An analyst said: "They will be looking for any active al Qaeda units, they went into Pakistan for retraining.

"They are also interested in any weaponry and any traces that Bin Laden will fulfil his boast to use chemical and biological warfare. They will also be keen to find any new documentation."