A New Jersey court on Wednesday heard opening arguments in a fraud case against a gay conversion therapy group operating in the state, which purported to offer the men a "cure" for homosexuality in exchange for thousands of dollars.

Four men and two of their mothers are suing the "non-profit" group Jews Offering New Alternatives for Healing (JONAH) for violated state consumer fraud laws by characterizing homosexuality as a mental disorder. Lawyers for the men said JONAH had claimed it could turn the gay men straight with therapy, but this was based on nothing but "junk science," the Associated Press reported.

Three of the plaintiffs are young men from Orthodox Jewish families in Brooklyn and the fourth, Michael Ferguson, is a Mormon who sought out JONAH.

"My clients needed help but JONAH lied and JONAH made it worse," plaintiffs' attorney David Diniello told jurors. "All they got was junk science and so-called cures."

An attorney representing JONAH said the men had left the conversion camp apparently content with the treatment and "on good terms," and that they did not complain until activists against gay conversion therapy approached them.

The conversion methods used by JONAH are also widely employed by other therapists across the US, the defendant's lawyer claimed.

JONAH purported to offer a "cure" for homosexuality, which it claims is a "learned behavior." The group charged up to $10,000 for conversion treatments, also known as reparative or reorientation therapy, it claims were based on science, despite respected members of the medicine and science community previously debunking key concepts of the therapy.

The American Psychiatric Association and American Psychological Association are among a list of organizations that have discredited conversion therapy and highlight its potential psychological dangers, particularly to young people.

The plaintiffs in the case claim that JONAH made them engage in a series of treatments that were unusual and unscientific. In some of the group sessions, the men were told to take off all their clothes and whack effigies of their mothers with a tennis racket, the Guardian reported.

The so-called therapists also screamed obscenities at the men, calling them "faggots," "homos" and "queer boys" in a locker room setting. The plaintiffs also say they underwent treatment that included being told to spend more time naked with their fathers, the AP reports.

JONAH has since been banned from operating in New Jersey and in other states, including California and the District of Columbia, and a push to ban the group nationwide has also received support from the White House.

Watch VICE's documentary Gay Conversion Therapy here: