"Significant failings" at all levels contributed to more than 1,000 patients being infected with the bug across three hospitals run by one NHS trust, a Healthcare Commission study found.

A total of 345 patients died after while infected with C diff, the infection being a definite contributing factor to their deaths in 124 cases, probably a factor in 55 and possibly a contributing factor in 62.

The number of deaths was far higher than declared by the Maidstone and Tunbridge Wells NHS Trust to the media and the Commission.

Inadequate staffing levels, dirty wards and too much focus on debts and Government targets all contributed to two serious outbreaks of C diff in the autumn of 2005 and early 2006, the study revealed.

Nurses were found to have told some patients with diarrhoea to "go in their beds".

The affected hospitals were the Kent and Sussex Hospital, Pembury Hospital and Maidstone Hospital. The watchdog has sent its report to the Health and Safety Executive and Kent Police, who will decide if there are grounds for criminal charges.

The trust's chief executive Rose Gibb left her job on Friday by mutual agreement with the trust's board.

The Trust was the subject of an undercover BBC investigation in May 2004 - months before the 2005 and 2006 outbreaks of C diff. It found evidence of blood stains ingrained on the floor and clinical waste skips containing bags full of old dressings and bodily fluids left open in corridors used by visitors and patients.

Dr Malcolm Stewart, medical director of the trust, apologised for the tragedy and said rates of C diff in the trust were now lower than the NHS average last year after improvements were made.