A HIGH flying Darwen businesswoman is at the centre of a 'multi-million dollar corporate fraud' investigation in Australia.

Helen Rosamond, 43, is being investigated after allegations a National Australian Bank employee obtained commissions for approving 'over-inflated invoices' to her executive events firm, Human Group.

Ms Rosamond had her home in Potts Point, New South Wales, raided on Tuesday morning, with documents and electronic storage devices seized by police.

Police also raided her North Sydney office and another premises was also searched as part of the operation.

Police are also reviewing what role, if any, was played by Rosemary Rogers, the former chief-of-staff to NAB chief executive Andrew Thorburn who worked for the bank for two decades.

As yet no charges have been brought.

Human Group is described on its website as providing "a holistic approach to creating and managing specialised executive projects and events.

Ms Rosamond – previously known as Helen Douglas and and Helen Fielding – went to St Wilfrid's CE School in Blackburn and has twin boys.

It is understood she emigrated to Australia after studying in East Lancashire.

Her Facebook profile shows she and her family have enjoyed luxury skiing and yachting trips.

NAB Chief Executive Officer Andrew Thorburn confirmed the raids involved a former supplier of the lender.

A statement on the bank's website said: "I want to let you know that, this morning, New South Wales Police informed us of the execution of a search warrant involving a former supplier of the bank.

"This matter has been investigated by us, and was reported quickly to police, and we will continue to fully cooperate with them. The people under investigation no longer work with the bank, or are involved with us. There are no customers involved or impacted.

"We will not be commenting further while this remains under police investigation.

"Our focus must remain on serving our customers with professionalism and integrity.”

A statement on the New South Wales Police website said: "Earlier this year, detectives from the State Crime Command’s Financial Crimes Squad established Strike Force Napthali to investigate allegations of corrupt commissions being paid for contracts.

"Investigators have been told about a scheme whereby a person would allegedly receive corrupt commissions to authorise payments by a financial institution of invoices for a contractor, which were in excess of the agreed value of the contract.

"As part of ongoing investigations, Strike Force Napthali detectives executed three search warrants at businesses at North Sydney and Milsons Point, and a home at Potts Point just after 9am on Tuesday April 10.

"During the warrants, investigators seized large amounts of documents and electronic storage devices, which will be examined by the squad’s forensic accountants.

"Investigations under Strike Force Napthali are ongoing."

Financial Crimes Squad Commander, Detective Superintendent Linda Howlett, said detectives were working closely with the financial institution’s investigators to establish exactly what has occurred.

She said: “Our Corporate Corruption Team has been working tirelessly to track payments and other funds to determine if an offence has been committee.

“From the information we have gathered so far, we know there are people who have significant information that may assist us, and we are appealing for them to come forward.

“These investigations are complex and often protracted, but it’s likely even a small piece of valuable information or insight could assist us in resolving the matter swiftly."