The UK’s first independent anti-slavery commissioner has said people need to have a much more open mind regarding who might be a modern-day slave, after a British woman told of how she was enslaved for 13 years.

In a new book called Secret Slave, the 44-year-old woman, who uses the pseudonym Anna Ruston, writes about meeting a taxi driver, whom she calls Malik, in 1987, when she was just 15. She claims Malik held her captive in his family home and subjected her to sadistic sexual and psychological abuse for more than a decade, beating and raping her and selling the four babies she had in captivity.

“[Anna’s] account shows just how real modern-day slavery is, how it’s happening in the UK,” Kevin Hyland told BBC Radio 4’s Today programme. “This isn’t something that’s happening miles away. We look at the most recent figures for up to June of last year and there’s been a sharp increase in the number of people from the UK who have entered into the NRM (national referral mechanism). It’s a big problem here.”

Anna was brought up by her grandmother but following her death the girl experienced years of neglect and abuse, including rape, by the time she was 11, the BBC reported. “[Malik] wasn’t anything to look at but the smile just made me feel comfort, I thought he likes me, he’s going to be kind to me and probably give me some affection which I never had,” she told Today.

“He said come and meet my mum for a cup of tea, and I didn’t think anything of it. I just got in the car and went to his house, and then I wanted to go home and I thought any minute now he’ll say: ‘Come on, get your shoes and we’ll take you home,’ but it never happened.”

During her captivity, Anna said she was in and out of hospital with horrific and sometimes life-threatening injuries, yet no one picked up on it.

“There was three or four people [with me] so I couldn’t speak, I never answered the doctors; I just shook my head. I just wish that if someone had left the room I could say to the doctor: ‘I’m being held, I need help.’ But they never left the room; if I went to the toilet they waited outside the door. At night time they sometimes slept in the room because they said that I needed looking after.”

It was when Malik’s family announced they were going to Pakistan and taking Anna with them that she made the decision to get out, and managed to slip a note unnoticed to a health visitor. The health visitor, she said, agreed to help Anna and arranged a date to be waiting outside the house in her car.

Despite escaping and subsequently being threatened by her kidnapper, who tracked her down, Anna, who now lives with her childhood flame and four children, still hasn’t given a statement to the police.

“It’s because I’m scared for my family, I’m scared he’s going to come after me and kidnap me again … If anyone goes missing I always think of him, has he done it, or has his family done it?” she said.

The story bears striking resemblance to that of Elisabeth Fritzl, who was held and abused for 24 years by her father, Josef Fritzl.

Hyland said it was alarming that no one recognised that Anna needed help. “I don’t think there’s a complete acceptance that modern-day slavery occurs. In fact, recent research done by Hull university identified that only eight out of 100 people believe that modern slavery actually was something that was a worry to them,” he said.

He also also reiterated calls for police to investigate cases of slavery without official contribution from the victim. “Sometimes there’s ways of collating evidence without a victim,” he said. “That’s why I’ve been saying continuously, and in my annual report to parliament this year, that this is serious organised crime, and policing needs to use the same techniques, the same level of resources like it does for other serious and organised crime.”

