For £20 a time, gypsy Linda Marks professed to be able to peer into the future. But it wasn’t her ability to tell fortunes that left the biggest impression: it was her habit of stealing them.

By appearing to conjure snakes and scorpions out of chickens’ eggs and turning water blood-red, the self-declared psychic frightened gullible clients into believing that their lives were blighted by wicked spirits.

The solution, she suggested, was for them to give her all their money so she could pray over it and "cleanse" it of evil - but once they did so, it would magically disappear.

A judge in Miami, Florida, sent Marks, 57, to prison for four years yesterday after she pleaded guilty to fraud. She will also serve three years of home supervision following her release and was ordered to repay more than £1.1 million to her victims.

"If she was any good, she’d have already known what her sentence was going to be," said Detective Toby Athol of Boynton Beach Police Department, who investigated the case.

"She gave her victims all these big stories, but she was unable to predict that I was coming round to arrest her, so I wouldn’t rate her psychic powers that highly."

Jack Makler, 64, who worked as a detective in Marks’ hometown of Delray Beach at the time of her crimes, was also due to be sentenced after he admitted to lying to state courts in an effort to help her avoid prosecution. In exchange, he received cash and gifts from Marks and her husband, Jimmy.

US District Court Judge Donald M.Middelbrooks heard how Marks, who sometimes went by the name of Gypsy Chawna or Reverend Jackson, promoted her services in supermarket freesheets and operated from a premises she called the Psychic Shop, in Delray Beach.

She preyed on the sick, the elderly and the vulnerable, telling them that their problems and illnesses stemmed from evil forces that only she could excise. Police believe that she may have reeled in hundreds of victims, but that many are too embarrassed to come forward.

"She falsely informed them that terrible things would happen unless they gave her thousands, tens of thousands and even hundreds of thousands of dollars to ‘cleanse,’" the indictment alleged.

"She would use various magicians’ tricks involving, among other things, snakes, scorpions and images emerging from eggs and the turning of clear water to the colour of blood in order to convince people of her powers of legitimacy."

Doubters were warned that their relatives would die from "terrible diseases such as Aids" and that those who were already sick would not get better unless they complied with her financial demands.

One elderly woman gave Marks £20,000 after being told that she had been "wealthy and evil in another life". Then the woman was told that her daughter had a terminal disease, so she remortgaged her home and handed over a further £7,500 so that it too could be purged.

Leroy Hoffert, who had just been told by doctors that he had six months to live when he first met Marks, emptied his bank account of £160,000 and gave it all to her after she said it would cure his cancer. He even complied with her suggestion that he buy her a new Cadillac "to pray in".

Mr Hoffert, who was 87 at the time, has since died. "She ruined my life," his widow, Delores, complained after Marks’s crimes came to light in 2002. "She took away anything I have to live on."

Marks complained: "The money had to be cursed, because it brought me nothing but darkness."

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