Rights group: Britons tortured after arrest on drug charges in UAE

(CNN) -- Three British men on holiday in the United Arab Emirates were beaten and subjected to electric shocks by police following their arrest on drug charges last July, a prisoners' rights group claims.

British citizens Grant Cameron, Karl Williams and Suneet Jeerh, all ages 25, have been in detention in Dubai for more than seven months.

They were arrested on charges of possession of the synthetic cannabis, "spice," according to Reprieve, a UK-based organization that provides legal support to prisoners.

Dubai police denied any torture took place.

The suspects were expected to be in a Dubai court Thursday morning for a first hearing in the case, said Marc Calcutt, a lawyer with Reprieve.

But the hearing was postponed until March 14 because witnesses failed to appear, Calcutt said.

Williams told Calcutt about the alleged abuse by Dubai police that he said occurred in a hotel room and the desert when the lawyer visited Dubai and was given "informal access" to Williams and Cameron.

"I remember that the police put a towel on my face so I could not see. They kept telling me I was going to die," Williams said in a statement released by Reprieve. "Then they took off the towel and I could see that there was a gun pointed at my head ... I started to believe that I was going to die in that room."

At one point, the police pulled his pants down and zapped his testicles with electric shocks, Williams alleged

The men were also pressured to sign documents in Arabic, without translation, after multiple beatings, Reprieve alleged.

The UK Foreign Office said it is aware of the allegations.

"We can confirm that we have been providing consular assistance to three British nationals detained in the UAE since July 2012. We have also been in close contact with Reprieve," the Foreign Office said. "The FCO takes all allegations of mistreatment and torture extremely seriously. With the individual's consent, we raise allegations of mistreatment with the relevant authorities and request that they conduct a full impartial and independent investigation."

The men are charged with consumption, which holds a minimum sentence of four years, and possession with intent to distribute, which could lead to 15 years in prison, Calcutt said. If they are charged with trafficking, they could face the death penalty.

Williams and Cameron came to Dubai to visit Jeerh who had moved there from the UK six weeks earlier, according to Calcutt. The three were driving a hired car and when they reached Jeerh's apartment building they were arrested. The three allege they were then taken to the desert and subsequently to William and Cameron's hotel where they claim the beatings and electric shocks occurred.

Calcutt also claims that Williams' hand was kicked until it was broken and says he has X-rays to prove it.