The civil servants say they are poorly paid

Staff at the Sheffield office staged an unofficial strike after a ninth manager was suspended by the Department for Work and Pensions (DWP).

The Public and Commercial Services Union (PCS) accused managers of deliberately inflaming the issue.

A manager based in Leeds was one of those previously suspended.

The Sheffield manager was suspended for refusing to conduct staff reviews under a performance development scheme, which the union claims is unfair and divisive.

Rather than fan the flames of industrial unrest ... we urge senior managers to sit down and find a negotiated outcome Mark Serwotka, PCS general secretary

PCS general secretary Mark Serwotka said: "Senior management, with their increasingly hard line and provocative stance, are deliberately seeking to inflame a worsening situation."

Managers have now been suspended in Sheffield, Leeds, London, Scotland and the North West.

Unions have called for urgent talks with the government to discuss relations within the industry.

Industrial unrest

Mr Serwotka said: "Rather than fan the flames of industrial unrest by suspending staff left right and centre, we urge senior managers to sit down and find a negotiated outcome."

The union is preparing to take the DWP to the high court, arguing the imposition of the pay scheme amounted to a breach of contract.

A spokeswoman for the DWP said: "If individuals are relieved from duty and subsequently agree to carry out their obligations, they will be welcomed back with open arms."