Audrey Ellis wept in the dock as she was found guilty of embezzling the cash over a four year period from St Mary's Surgery, on Lytham Road, South Shore.

Ellis, 52, of Hill Crescent, Newton, who was in charge of accounting, staff payments and petty cash at the surgery, denied a total of 31 offences – 17 of theft and 14 of false accounting.

But a jury at Preston Crown Court found her guilty of all charges.

PC Ed Kealey, of Blackpool police, said: "In the end this was just a case of greed getting the better of her.

"It has been a complete abuse of the position of trust that was put in her at work.

"We still don't know why she has done it because she has never admitted any wrongdoing. I don't think she'll ever admit she has done it even though she's been found guilty.

"By the end of it I think she had even convinced herself that she had done nothing wrong."

Ellis had been practice manager at the surgery from 2000 to 2006 when she left.

Ellis had been paying herself more than she should have and falsifying accounts. She also used money from the practice account to pay a gas bill for her sister's hair salon.

The court was told she had "doubled" cheques, meaning she had made payments to suppliers and then duplicated and altered invoices.

The cheques were then created again and cashed by herself. She is also alleged to have claimed unwarranted expenses and overtime.

"I never cashed a cheque and kept the money at all, ever," she told the court in her evidence.

"I never received any money and never took any money."

The investigation into the thefts only began after Ellis left and her replacement looked at payroll software and believed she had paid herself more than she should have.

Auditors from Blackpool Primary Care Trust were then called in.

Ellis, who was bailed, has been told to expect to be jailed when she is sentenced on October 2.