The horror that will be felt across the country at yesterday’s events in Westminster is impossible to adequately put into words.
The murder of a police officer on what should have been a routine day on duty protecting the public. The senseless killing of other, innocent passers-by as they quietly went about their own private business.
It all could have been so much worse. Moments before the attack a party of happy schoolchildren were getting their photo taken on the bridge with Big Ben in the background.
The fact this terrible event happened in a place that we all know so well - familiar as the backdrop of nightly television new bulletins and from sightseeing and business trips to London - somehow makes it all the more frightening.
That of course is the point, the reason presumably why the attacker chose to strike at such a symbolic spot, at the heart of our democracy. We are supposed to be frightened, cowed by the awful and indiscriminate violence.
Even amid the carnage, the response has been inspiring. Members of the public rushing to help the injured and dying before the emergency services arrived on the scene. For today our hearts go out to those who have lost loved ones.