London, September 9 (RHC)-- UK Defense Secretary Michael Fallon says London would not hesitate to carry out more secret drone attacks on British militants in Syria. His statements come one day after UK Prime Minister David Cameron revealed that British forces have killed three Daesh terrorists, including two young Britons, in the northern Syrian city of Raqqah in a drone airstrike.

Addressing the parliament, Cameron further elaborated that the main target of the drone attack was 21-year-old Reyaad Khan from the city of Cardiff, but the August 21st airstrike also killed two other Daesh terrorists, including another British citizen identified as 26-year-old Ruhul Amin.

Fallon described the attack as "perfectly legal act of self defense," saying the men were terrorists who'd been planning a series of attacks. Fallon said: "We don't have general permission [from parliament] to carry out military operations in Syria, but at the time of the debate last year, the prime minister made it extremely clear that where there was a vital national interest at stake we wouldn't hesitate to take action rather than seek prior permission."

The strike was carried out without the parliament's approval. Critics dismissed the unauthorized strike as unprecedented and deeply worrying. Amnesty International also criticized the move, saying the UK has been conducting summary executions from the air.