PHOENIX -- Twenty-four former members of Dahn Yoga are suing the organization in federal court, accusing it of fraud and psychological manipulation through thought reform, sleep deprivation and excessive exercise.

Dahn Yoga, which is based in Korea, says it uses an exercise system that promotes physical, spiritual and emotional well-being.

Former member Amy Shipley, however, disagrees.

"I think that Dahn Yoga is an extremely deceptive and very dangerous cult," she said.

While she was a member, Shipley rose through the ranks, eventually achieving the status of Dahn Master and spending $47,000 in the process.

"(Members) pay for the privilege of being brainwashed," said Ryan Kent, who represents the plaintiffs in the lawsuit.

According to Kent, Ilchi Lee, the person in charge of Dahn Yoga, earns about $1 million per month off employees and new members.

"They're lying to these kids," Kent said. "They're concealing the true nature of the organization."

In addition to the fraud accusations is an allegation that Lee raped an employee.

Dahn Yoga spokesman Joseph Alexander said the accusations are false.

"Adding the sexual assault claim only increases the negative publicity which (the plaintiffs) thought would pressure us into offering them money," Alexander said.

"These are adults -- very intelligent people who have chosen to become part of this program," Alexander said. "As I said, no one was tortured or forced to participate."

The organization has asked the court to dismiss the case, saying several of the plaintiffs had already taken cash settlements and agreed not to sue Dahn Yoga in the future.

This is not the first time Dahn Yoga has faced scrutiny. Three years ago, a 5 Investigates report focused on a death near the organization's Sedona retreat.

Julia Siverls, 41, collapsed and died during an exercise on the side of a mountain. Her brother Robert Siverls said she told him she was afraid to go on the hike.

Dahn Yoga representatives denied any responsibility for the death.

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