JOHANNESBURG/LONDON (Reuters) - British security group G4S denied that its workers had electrocuted and drugged prisoners at South Africa's Mangaung prison, the maximum security facility it ran before the government stepped in to restore order earlier this month.
The Wits Justice Project said some prisoners were forcibly injected with anti-psychotic medication and subjected to electric shocks.
"We do not use any form of torture or shock treatment," a G4S spokeswoman said on Monday.
She said the staff also did not have access to medication and they did not administer drugs: "All medical decisions for inmates are handled and addressed by independent certified medical staff."
The abuse allegations at Mangaung - the second-largest privately run prison in the world according to G4S - follow scandals at the British company such as failing to provide enough guards at the London 2012 Olympics and discrepancies in tagging prisoners in Britain.
Ruth Hopkins, an investigative journalist with the Wits Justice Project, said she had documented cases of beatings - including electroshocking - involving about 30 inmates. She had also documented about 20 cases of forced injections of anti-psychotic drugs.
"A pattern that emerged throughout my investigation is that inmates who were considered difficult or who were involved in some problem, they would take them to the single cells in the prison, strip them naked, pour water over them, put them on a metal bed frame and use these electroshock shields to shock them," she told Reuters.
The Wits Justice Project is part of the Journalism Department of the University of Witwatersrand in Johannesburg and investigates alleged cases of mistreatment and miscarriage of justice in South Africa's prisons and justice system.
In a formal statement reacting to the most recent allegations, South Africa's Correctional Services Minister, Sibusiso Ndebele, promised an exhaustive investigation.
"As the Department of Correctional Services (DCS), we view these allegations, of forcibly injecting offenders with antipsychotic medication and using electroshocks to subdue and control them, in a very serious light," he said.
"We will leave no stone unturned in this investigation, in order to ensure that those implicated in such inhumane acts face the consequences of their actions."
The allegations came after South Africa's Department of Correctional Services took over the facility on October 9 because the private security firm "lost effective control" of the 3,000-inmate establishment, a senior prisons official said on Monday.
James Smalberger, Chief Deputy Commissioner of Incarceration and Corrections, said safety and security issues at the prison were under scrutiny well before the most recent allegations.
"There were assaults, there was labour unrest, there were hostage situations, that were a clear indication that there was not effective control," Smalberger told Reuters.
All of these issues, in addition to the latest allegations made by the Wits group, were now the subject of an ongoing official investigation into the management of the Mangaung Private Correctional Centre, which had been run by G4S, the world's biggest security firm, since 2001.
"When you have a contract, there are requirements that you must comply with ... if there are assaults, obviously it becomes a breach of contract," said Smalberger.
Smalberger did not say his department had confirmed the mistreatment allegations made by the Wits group. The department was looking into them as part of its overall investigation into the G4S management of the prison.
The problems at the facility were exacerbated when G4S dismissed more than 300 of its workers after a labour dispute.
The company said on Monday that it asked the Department of Correctional Services for assistance to manage the prison, and it decided step in and to manage the prison on an interim basis. "We are very happy to have their help," the spokeswoman said.
G4S head of operations in Africa, Andy Baker, told BBC radio on Monday that he expects G4S to be given back control of the prison in the near future.
"If we are presented with evidential support of some of the statements that are being made we will look at it comprehensively," he said.
"It's difficult in an environment with so many people and so many moving parts to categorically state that there has never been somebody stepping over the line. To my knowledge there has never been an abuse of this type of nature."
Mangaung was only one of two prisons, out of the 243 correctional facilities in South Africa, that were privately run, Smalberger said.
The South African government had decided in 2010 not to pursue or further expand a policy of public/private partnerships in the running of prisons.
Editing by Giles Elgood