The Brussels terrorists were preparing an attack on a nuclear power plant and had recorded 12 hours of reconnaissance footage, it has been reported.
Hours of film of the home of the Research and Development Director of the Belgian Nuclear Programme were discovered in an apartment in Brussels raided by anti-terrorist police following the attack in Paris.
The footage confounded investigators at first - as it showed the entrance to the director’s home in Flanders, an area outside the capital.
But detectives made the chilling deduction that the group was attempting to gain entry to an atomic facility after watching all 12 hours of footage, which included images of a local bus.
Armed troops were sent to defend French and Belgian nuclear facilities following the discovery and both countries nuclear programmes were put on the highest state of alert.
Reports of the plan first emerged as early as February and was at that time linked back to the cell responsible for the Paris attacks.
The footage was discovered 'as part of seizures made following the Paris attacks,' a Belgian prosecutor said, refusing to divulge the individual's identity 'for obvious security reasons'.
At the time, Belgium's federal agency for nuclear control stressed the importance of not revealing the name of the person involved so as 'not to endanger the enquiry or nuclear security' or indeed the person involved and their family.
The images were captured by a camera hidden in nearby bushes and recovered by two suspects who left the area in a vehicle with the lights off, Derniere Heure reported.