Yes they know it and don't want to publicly admit it, just like over here the Government only admits that an attack was a Terrorist Attack when it doesn't have any realistic option.

Governments always use BS to Pacify the Sheep and keep them as uninformed as possible.

I believe that the Probability of more attacks occurring here maybe even Terrorism by Truck is not just likely but near 100%, the only thing I am not sure of is how many attacks will occur and the timing of the attacks.