Women are rescued from sex traffickers
The women – six from China and one from Romania – were suffering "awful" sexual abuse and exploitation before they were rescued by Leicestershire police.
They were discovered in the course of separate investigations by Leicestershire detectives in the past two years.
A force response to a Leicester Mercury Freedom of Information Act request also revealed officers had encountered other women thought to have been trafficked and forced into the vice trade. However, it is understood that those women were too frightened to speak to police.
Leicestershire's assistant chief constable, Chris Eyre, said some of the women entered the country legally. Others were smuggled in on forged documents. Some had believed they were going to be working in bars, hotels or clubs.
There is also evidence of the women being told their families at home would be harmed if they did not agree to work.
Mr Eyre, who will become the force's deputy chief constable in the new year, said: "The abuses taking place are awful.
"I don't like it, but there are women who choose to work in prostitution – but this is on a different scale completely. These women have been forced to work.
"We've had cases of women living in locked rooms, literally being used as assets that are moved around and systematically abused."
Leicestershire police previously "rescued2 23 trafficked women under the nationwide Operation Pentameter 1, in 2006.
Police have appealed to women working as prostitutes and brothel owners to notify police if they suspect a woman is working against her will.
Maria, 24, was smuggled to London, from Albania, when she was 13.
She told her story through Poppy Project, the Home Office-funded refuge in London which has offered accommodation to women rescued in Leicestershire.
She was forced to have sex with up to 70 clients a day.
Maria said: "I have been raped, beaten, sold, cut with knives and threatened. I have scars and I am depressed.
"The men who came to me were of all different nationalities. I did not ask any of them for help, I was too frightened.
"My traffickers threatened to kill me and they threatened to take my sister, too, and do the same to her."
Poppy Project spokeswoman Anna Bowden said: "I can guarantee there are other women in Leicestershire who have been trafficked as prostitutes."

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