Three managers at an NHS hospital cleaning company were arrested today on suspicion of blackmailing foreign colleagues.
The trio were held as police raided the office of ISS Mediclean at Kingston Hospital, in south west London.
The move followed several weeks of investigation after a tip-off that senior managers were blackmailing junior members of staff.
It is understood the alleged conspiracy targeted foreign employees who were threatened with being reported to immigration authorities.
Detectives at Kingston CID brought in officials from the UK Border Agency after fears arose some staff were working illegally.
It is understood the initial information came from a community group, the Kingston Race and Equalities Council, that works to tackle racism.
A Metropolitan Police spokesman said two men, aged 47 and 43, and a 28-year-old woman were being questioned tonight.
He said: "Kingston Police conducted a pre-planned operation to arrest three individuals for alleged blackmail offences."
A hospital spokeswoman said: "The trust is grateful to the police and the UK Border Agency for the attention and priority they have given to this issue.
"This is now a police matter and so we are unable to make any further comment for fear of prejudicing the investigation."
An ISS spokesman said the company is "co-operating fully" with the inquiries that are under way.
He added: "ISS deeply regrets any adverse reaction that this incident may have had on the patients, staff and visitors to the hospital.
"However, it is our responsibility to work within the law and to ensure that our employees do the same, which includes demonstrating their right to work legally.
"Immediate steps have been taken to ensure that the correct levels of management and staff remain in place and ISS are keen to assure everyone that this action will have no effect on the high standards of service that are expected throughout the hospital."
ISS Mediclean is part of the ISS group that employs more than 43,000 staff at NHS and private hospitals across Britain.Reuse content