WATCH ROLE-PLAY: Chemical attack in Slough

WATCH THE VIDEO (1 available - click to expand)

Video 1

A devastating attack took place on Sunday when sodium cyanide was released through the ventilation system at Slough's Queensmere Shopping Centre.

But the affects it had on the public were purely acting, as this was a massive decontamination exercise in which all the emergency services came together to practice, should such an event ever occur.

Our video team were at the scene of the exercise.