Within four minutes they were at the junction and pulled into a petrol station forecourt. Rehman switched the blue light off and waited. The vehicle was new and the plastic smell of a new car hung in his nostrils.

‘Target is now on the A58 heading east, approximately three minutes from your location,’ the voice from CT ops told him.

He stared at the vehicles coming past the forecourt from the right and rehearsed the manoeuvre in his mind. He would need to time this perfectly. The surveillance car – a black BMW – had got into position behind the ambulance a few minutes earlier. If, as expected, the ambulance continued on its route, it would pass the petrol station and Rehman was in the ideal spot to pull out into the road and get himself one or two vehicles behind it.

He looked at the dashboard clock. Less than a minute. Now thirty seconds. And there it was, in his wing mirror, a few seconds away. ‘Couldn’t be easier to spot if they’d stuck a flag on top,’ Rehman said, half to himself, half to the passengers.

As the ambulance passed the forecourt, he got a glimpse of the driver, a stocky man with a shock of dark hair. A black unmarked BMW – which Rehman recognised as the surveillance car – was driving two vehicles behind the ambulance. It slowed as it approached the forecourt, allowing Rehman to pull out aggressively and squeeze into the gap. Cheers, mate, he said silently to the surveillance car, now behind him.

He spoke to the ops room. ‘We’re in position. Two vehicles behind the target.’

They were driving slowly, stopping and starting along a residential street, square red-brick houses set back from the road behind tall railings on one side, mobile-phone shops and takeaways breaking up the houses.

Rehman knew that a few hundred metres ahead, a pair of unmarked police cars would be pulling into the road and blocking the traffic. He imagined, rather than heard, the honking of irritated drivers somewhere in front of him as the traffic slowed and came to a halt. That jam would now be rippling backwards down the road. Any second now. And yes. There, the brake lights on the ambulance came on. They were all slowing down. And stopping. Good work, he thought.

#

Glenister had driven ambulances before, but never anything as flash as this. He fiddled with the radio, trying to get a signal, then gave up in frustration. The sweatshirt they had pulled off the driver in the bathroom was a size too small and the material was pulling across his shoulders.

But at least he was outside. It was his first trip out since he’d arrived in Leeds five days earlier. After fleeing the scene of the Pall Mall attack, he had first made his way to Birmingham, then caught a slow train to Leeds. The last five nights had been spent in the NRF’s safe house in the ghost estate in the company of a man who called himself Roger, a portly man who spoke little and who was now in the passenger seat chewing his moustache.