Ominous article about the largest counter-terrorism exercise to date, including a 'gold commander','officers who came on shift this morning knew they were taking part in an exercise - but nothing about what they would be facing' and 'Although the nature of this "live play" exercise sounds similar to the attack in Tunisia, this event has been six months in the planning'.

'Senior officers say that while much of the exercise will be hidden from view, there may be occasions when the public hear loud noises or see areas being cordoned off.'