Council chiefs are investigating after two social workers blew the whistle on what they claim is ‘a culture of bullying, threats and intimidation’ at Cheshire East.

In an open letter to council chief executive, Erika Wenzel, fellow social workers and councillors, the disgruntled workers said they had to bring their concerns about the department to public attention.

In the anonymous letter, also sent to the Express, the staff claim pressure is making their jobs unbearable and described two named members of staff as ‘the worst example of school yard bullies’.

The council said it was disappointed that the workers had gone public and admitted it had been tackling ‘shortcomings’ in social care since 2009. But it said it had invested heavily and was seen as ‘performing well’ by the national regulator.

The letter said: "We are two social workers who have the misfortune to work for Cheshire East council. We are working under extreme pressure with excessive case-loads.

"The vast majority of workers take work home with them, work long hours, yet instead of receiving support, we see the exact opposite. We see individuals singled out for spiteful attention. We see increasing numbers of staff taking sick leave option, stress levels are increasing and staff, even in these challenging times, are looking to leave Cheshire East and move into positions where they will feel valued.

"When we worked for Cheshire County Council we worked for an organisation that was respected both externally and internally, now we work for an organisation whose reputation is diminishing and whose senior management have no respect for it’s work force."

However, the council said only six out of 828 staff working in children’s services – less than one per cent – were off work with stress-related illness.

Lorraine Butcher, director of children and family services at CEC, said: "It is disappointing that two social workers have chosen to express their concerns about perceived problems in the service very publicly and anonymously and have ignored the range of avenues available within the workplace to address any such issues.

"Staff can raise concerns through their line manager or grandparent manager, using grievance procedures, contacting their union or other representation and, if they wish to remain anonymous, through whistle-blowing procedures."

It is understood the council was unaware of the allegations until the letter was received.

CEC staff can fill in ‘concern’ forms anonymously and have their details kept confidential. It only recommends going to external organisations such as trade unions if concerns are not addressed satisfactorily.

Ms Butcher said she also holds regular meeting with staff where they can raise issues directly with her.