The survey for the trade union Unison found civilian employees, such as control room staff and secretaries, left their jobs because of bullying by managers or uniformed officers.

It said some had even considered suicide.

Two thirds of support staff have suffered or witnessed bullying, according to a poll of 690 workers in England, Wales and Scotland, but excluding London.

The survey also found two-thirds were bullied by managers and almost half by police officers.

Series of incidents

Victims reported a series of incidents including being timed on breaks, shouted at, intimidated or constantly criticised.

Most of those who responded to the survey said workplace bullying was widespread and was increasing.

Unison general secretary Rodney Bickerstaffe said: "Bullying should not be all part of the day's work - it demeans those who bully and those who are bullied.

"A new culture is needed in Britain's police forces to make sure that people are treated with respect and dignity."