Debt collectors have been sent out to doctors and hospital staff across east London after they were overpaid by a combined total of nearly �1million for two years running.

Barts Health NHS Trust made a series of administrative errors that meant staff were overpaid at the Royal London Hospital in Whitechapel, the London Chest Hospital in Bethnal Green, and St Bartholomew’s Hospital in the City.

An audit released by the trust said a debt-collection agency was employed to try to reclaim the money after 329 salary overpayments worth �971,000 were paid out in the 2010/11 financial year, while an additional �995,000 was incorrectly shelled out on wages in the last financial year, up to April 2012.

In one case, a doctor was paid an extra �4,000 a month for on-call duties they were no longer performing, according to the documents which were obtained in a Freedom of Information request by the Health Service Journal, a magazine for NHS workers. .

A spokeswoman for the trust, which was created in April last year after the merger of three existing trusts - Newham University NHS, London NHS, and Whipps Cross University NHS - said the mistakes happened when staff left or changed their hours or duties and the information was not passed to the payroll department promptly.

She said the �995,000 equates to just 0.25 per cent of the total salary bill of �393m, and added: “The majority of this amount has either been recovered or been fully accounted for, with just 27 per cent of the total - �275,580 - still outstanding and being actively pursued.”

It’s understood a number of employees are having deductions taken from their salaries, while some ex-staff are being pursued by debt collectors. The trust is piloting a new electronic system in an attempt to prevent the problem this year, the spokeswoman said.

“We rigorously pursue all salary overpayments and are confident that this new additional measure will help further to avoid their occurrence in the first place,” she added.