Up to 60 Taliban fighters have been killed in operations supported by the UK Royal Air Force's armed General Atomics MQ-9 Reaper (Predator B) unmanned air vehicles.
A senior source from the RAF's Creech AFB, Nevada-based 39 Sqn gave figures of "40 to 60" enemy losses when speaking at the Shephard UV Europe conference in London on 9 July.
Reapers operated by 39 Sqn Reaper have now "engaged on numerous occasions", and the officer confirmed that "we have now employed both weapons".
The RAF's Reapers typically carry four Lockheed Martin AGM-114 Hellfire missiles and two Raytheon GBU-12 226kg (500lb) laser-guided bombs. The type began armed operations within a few months of beginning their primary role of providing persistent surveillance for coalition forces late last year.
The squadron source said that in Afghanistan in late May a Reaper's infrared sensors detected a 100 litre (26USgal) culvert bomb, and the UAV's operators also helped to find the trigger man hiding inside a nearby parked car.
In separate incidents involving a US Air Force Reaper and an RAF-controlled MQ-1 Predator, UK personnel stopped actions that would have caused "blue-on-blue" losses and collateral damage by identifying a coalition special forces team that had been thought to be insurgents and a house that was known to contain women and children.