On behalf of 2,300 UK controllers, Prospect aviation officer, David Luxton, said:

"Our deepest condolences go out to the family, friends and work colleagues of this controller. But this stabbing is even more deplorable if it proves to be linked to the appalling tragedy that took place in 2002, as such acts do nothing to help the ongoing investigation into the crash or inform improvements to minimise risk and prevent future accidents.

"It is further vindication of the UK’s system of anonymous and non-punitive reporting of any risks and accidents to ensure lessons can be learnt from every incident.

"The UK has an exemplary safety record in some of the busiest air space in the world and Prospect, along with NATS, the CAA and other interested parties, is constantly working to maintain that safety record.

"As in all walks of life, air traffic control has inherent risks but the aim is to minimise risks and prevent future accidents. Acts such as this senseless killing do nothing to assist the drive to improve air safety."