Bullying and sexual harassment are totally unacceptable, and I am determined to root them out

Martin Narey, Prison Service

Several disciplinary inquiries have begun following the allegations.

"Intimidation and bullying were practised by many individuals and groups both sporadically and systematically," a Prison Service spokesman said.

"The impact on staff was widespread and destructive and having a detrimental effect on the performance of the prison.

"There was a specifically sexual dimension to this culture."

The bullying involved men and women, the inquiry has revealed.

It began last October after Holloway's then governor David Lancaster raised the concerns.

New governor

Mr Narey has ordered an immediate management overhaul at the prison, which holds up to 532 prisoners.

Nine middle managers, believed to be senior officer or principal officer grades, have been "compulsorily posted" to other prisons.

Seven of them had been removed immediately after the investigation began. The others were transferred on Friday.

A new senior management team is being installed at the prison to enable it to "move forward", said Mr Narey.

None of these members of staff, whose role would have been to help control the middle management, have been implicated in the allegations.

Holloway also has a new governor Edd Willetts, who was appointed just before Christmas.

'Robust management'

Mr Narey said the alleged behaviour had not been properly challenged until now.

He said: "Behaviour of this kind will not be tolerated in the Prison Service.

"Management should be tough. It should be robust. But it should never be intimidating.

"Bullying and sexual harassment are totally unacceptable, and I am determined to root them out."

The Prison Service is not identifying the staff involved or the new prisons they have been transferred to.

Mr Narey said: "I am confident that the overwhelming majority of staff at Holloway who are committed to the care of prisoners will welcome the action we have taken."