‘Scared the life out of me, it did.’ The interruption came from a woman who was sitting nearby. ‘I hope no-one was in there.’

I introduced myself, and tried to reassure her. ‘While we’ve got the interpreter here,’ I said to her, ‘can I speak to this young lad? If you go with DS Maguire, he’ll ask you a few questions.’

‘If you like, dear,’ she said, looking mildly put out for a second before beaming at Dan’s youthful, squaddie appearance and running her hand over her hair.

I gestured Dan over and shifted my attention to the boy who had been sitting next to her. ‘What’s your name?’

‘Ali.’ He shrugged. ‘I need go.’

Dougie was right about him being nervous. Shock from the fire and the gash, probably. The cut had been stitched, and traces of congealed blood were smeared over his childlike features. ‘I’m Maya. Rima is going to translate, OK?’

His nod was fast. He was chewing at the skin round his finger nails. ‘My parent be worry. I need go.’

‘I’ll be as quick as I can.’

Rima translated.

‘Were you already here when the flash mob started?’

He shook his head. From his height and build I guessed he was about ten, but the expression in his eyes could have put him at three times that age. He pulled himself up straight as though wanting to shake off the fear he knew I’d seen.

‘You aren’t in any trouble.’ I kept my voice as gentle as I could and waited for him to relax. ‘Can you tell me what you saw?’

His face held its silence but his eyes didn’t. He stared at Rima as though he was hoping she’d understand something. ‘Was just bit fun.’ He didn’t wait for the translation. He fixed dark eyes on me, and it hit me how vulnerable he seemed. ‘Dance. Music. Is all.’ He pointed his nose away from me, dismissive and disinterested.

The burnt-out building was a mere shell, the damage self-evident. I wanted to say that it wasn’t fun for the people who’d been hurt and lost their livelihoods, but he was just a kid, and I needed to focus on getting what key information I could. ‘What was the flash mob about?’

Rima spoke gently.

Ali shifted forward so that his feet were on the ground, and pawed at the laminate flooring with his scruffy trainer. He gabbled in Arabic, and gestured pleadingly to Rima with his eyes.

‘He says he doesn’t know anything about the flash mob. He was there. It started up. That’s it.’ Rima’s frown suggested she wasn’t convinced.

‘Who brought the speakers?’

Rima translated.

‘He doesn’t know.’ He was avoiding my gaze, and his spindly leg was jigging up and down. His white trainers had broken laces, and were covered in scuff marks, and he wasn’t wearing any socks.