Six police accused of torturing suspects by simulated drowning

Six officers have been suspended over allegations they ducked suspects' heads in buckets of water during a drugs raids.

The Independent Police Complaints Commission is investigating the claims which form part of the biggest corruption inquiry launched by the Yard in recent years.

The alleged victims were foreign nationals seized in Edmonton by members of the Enfield crime squad.

Senior Met officers are said to be "horrified" by the claims. One insider said: "The allegations are very disturbing. This was not waterboarding Guantanamo Bay-style, no-one is saying they were tied to boards but this is still very serious.

"These officers seem to be part of a rogue squad which was out of control and they need to be kicked out of the force."

Officers found guilty could also face possible criminal charges including assault.

The claims, thought to have been first made by a serving police officer, are another blow for Met Commissioner Sir Paul Stephenson who has faced a series of controversies since he took charge four months ago.

They are particularly embarrassing as Met officers are investigating claims by former Guantanamo detainee Binyam Mohamed that he was tortured while in US custody.

Senior officers have known about the allegations for some weeks and Sir Paul has ordered a new regime of "intrusive supervision" across the force. The borough commander of Enfield, Chf Supt Adrian Hanstock, has been transferred though it is not suggested he knew about the crime squad's alleged activities.

A wider investigation into the squad includes accusations that evidence was fabricated and property stolen from suspects.

Nine detectives - virtually the entire squad - were suspended in February over allegations that goods including iPods and flat screen TVs were taken from suspects.

The torture claims involve an allegation by at least one suspect that their head was ducked into a bucket or tank of water.

The claims - involving six of the officers - led to the abandonment of a drugs trial involving the four men and one woman held in the drugs raid last November.

Police had said they found a large amount of cannabis and the suspects were charged with drug smuggling.

The case was abandoned four months later when the Crown Prosecution Service said "it would not have been in the public interest to proceed". It is understood the trial, by revealing the torture claims, would have compromised the criminal investigation into the officers.

A Met spokesman said an employee had raised concerns about a small number of officers during an internal investigation into allegations of mishandling of property.

He added: "The Met's Directorate of Professional Standards then initiated a thorough investigation and as part of this made a referral to the IPCC in April.

"Whilst the investigation is ongoing it is not appropriate to make assumptions. That said, these are serious allegations that do raise real concern.

"The Met does not tolerate conduct which falls below the standards that the public and the many outstanding Met officers and staff expect.

"Any allegations of such behaviour are treated very seriously and if found true the strongest possible action will be taken."