She is then seen with a thin length of thread coming out of her mouth while her dad gets ready to fly the drone.

Robots are being prepared for increasingly sophisticated roles in combat, in the form of remotely operated drones and ground-based vehicles mounted with machine guns and grenades.

The Reaper was flying a combat mission when operators lost "positive control" of the UAV, or the ability to establish connections and send control inputs to the remote-controlled aircraft.