The young WPC nodded her confirmation. Frost waved a hand for the girl to continue.

‘To save time I cut through the multi-storey car park in the town centre – it saves walking all the way round the block.’

‘Bleeding dangerous at that time of night,’ muttered Frost. ‘If it’s the same bloke, he got one other girl there.’ The car park was always dark and cold, and after the shops had closed, very echoing and empty.

‘I couldn’t face my mum’s nagging if I got in late. She’s very strict.’

‘Not always a bad thing,’ said Frost, his hand caressing the cigarette packet in his pocket. God, he was dying for a fag. ‘Then what?’

She screwed up her face and shuddered at the memory. ‘I was hurrying. At first I couldn’t hear anything, just water dripping somewhere and the echo of my own footsteps. Then – and I had to stop to make sure – I could hear footsteps behind me. Quiet footsteps as if whoever was making them didn’t want to be heard. I walked faster. The footsteps quickened. Then, suddenly, he was right behind me. He clamped a hand round my mouth. I tried to bite his hand but he punched me – hard.’ She was shaking violently and had to pause to compose herself.

‘Take your time, love,’ soothed Frost. ‘When you’re ready.. .’

‘He said, “Scream, you bitch, and I’ll kill you.” She shook her head. ‘I don’t think I could have screamed, even if I’d tried. I was paralysed with fear.’ She paused again.

Frost waited a moment for her to calm down. ‘When he spoke, how did he sound? Old, young, any sort of an accent?’

Sally shook her head again. ‘Youngish I think. Twenty – thirty perhaps… I don’t know. He was trying to sound Irish, but you could tell he was putting it on.’

Frost nodded. It was the same bloke. The other victims had reported the same.

‘He pulled a cloth thing over my head so I couldn’t see, then grabbed my hair and kicked my legs so I fell to the ground. Then he pulled up my clothes… He…’ She faltered, then, shoulders shaking, broke down in tears.