The woman at the desk didn’t recognise the pictures.

‘Sorry. And I’d remember him.’ She pointed to Abu Mujahid’s face. ‘Try the Spar over the road? Mr Gill is a real curtain-twitcher. He sees everything and doesn’t mind telling you about it.’

Mr Gill sounds a real pain in the arse, thought Jenson as she thanked the woman and crossed over the road, where they were greeted by a chubby elderly man with a grey beard and tiny round glasses.

Jenson introduced herself and showed the pictures. Mr Gill scrutinised them.

‘Not seen him – or them,’ he said flicking through them. He stopped at the image of Abu Mujahid. ‘Ah. I know him. He moved in a few days ago – always in and out, in and out, like he can never make up his bloody mind.’

Jenson could barely repress her excitement. She’d done enough door-to-door inquiries to know how rare it was to get a result. ‘Where have you seen him, Mr Gill? This is really important.’

‘Over there – that block of flats on the corner. The yellow-brick one. I was working in the office, up there.’ He pointed to the ceiling. ‘My wife was running the till. I say running, she was on the bloody phone the whole time. Out he comes – then twenty minutes later, he goes back in. In and out all day. Can’t have a proper job. I thought he dressed odd – like a white guy pretending to be Asian, if you know what I mean. You don’t see so much of that.’

That’s him, thought Jenson. That’s Abu sodding Mujahid. She was desperate to radio in, but needed to keep Mr Gill talking for a moment longer. ‘Do you know how long he’s been there, Mr Gill?’ she said. Her heart felt like it was bursting in her chest.

‘Only a few days. Maybe since Monday or Tuesday. But he’s in that block. I’d swear on my mother’s grave.’

#

Special Operations Room, Lambeth, London

The command team were assembled around the conference room. A woman Tennant didn’t know introduced herself as the Met’s tactical adviser on drones, Amanda Elliott. ‘Let’s keep this brief,’ said Tennant. ‘Options for stopping a drone attack. What have we got?’

Elliott pulled out a file.

‘Over the years we’ve tried a number of approaches on drones, sir, both kinetic and electronic,’ she said. Tennant suppressed his amusement at the use of military euphemisms.

‘All work to some extent, but nothing is universal. If a drone is on a preprogrammed course, there may be no signal to jam, although you can sometimes take electronic control. If it’s being flown by remote radio control, then we have a greater chance of electronic intervention, but jamming the signal is not always successful.

‘We’ve got a jamming kit on its way to Wembley. We know the model of drone that the cell is using and that gives us a good head start. But they may well have adapted the radio control units. My assessment is only a fifty per cent chance of success.’