Antiguan staff of the auditor of Stanford International Bank,the institution at the centre of an $8bn (£5.6bn) fraud investigation have said they do not know where the owner of the firm is.

A staff member at its Antiguan division of CAS Hewlett confirmed the company was run by Celia Hewlett, who took over after her father Charlesworth 'Shelly' Hewlett passed away last month, but he said her whereabouts were unknown.

'She has not been here for about the last two weeks,' he told Accountancy Age.

He added that he did not know when she was expected back, but confirmed that the firm was still the auditor for SIB and they had not so far come under the SEC's spotlight. 'The SEC has not been in contact.'

Allen Stanford, the cricket-loving billionaire owner of SIB has been charged by the SEC with perpetrating the massive fraud, linked to high-interest investments known as Certificates of Deposit.

CAS is a small firm with offices in London and one in Antigua where SIB is based.

CAS gave SIB an unqualified audit opinion in signing off its most recent annual report last April.

CDs are thought of as one of the safest types of investment vehicles.

The investments pay interest on money in a similar way to a savings account, but the returns are typically higher with a CD.

In a statement the SEC said: 'The defendants have misrepresented to CD purchasers that their deposits are safe, falsely claiming that the bank re-invests client funds primarily in 'liquid' financial instruments (the portfolio); monitors the portfolio through a team of 20-plus analysts; and is subject to yearly audits by Antiguan regulators.'

The SEC also charged SIB chief financial officer James Davis, Stanford's college room-mate, in the enforcement action.

The SEC has been granted a temporary restraining order which froze the defendants’ assets, and appointed a receiver to marshal those assets.

'As we allege in our complaint, Stanford and the close circle of family and friends with whom he runs his businesses perpetrated a massive fraud based on false promises and fabricated historical return data to prey on investors,' said Linda Chatman Thomsen, director of the SEC’s Division of Enforcement.

'We are moving quickly and decisively in this enforcement action to stop this fraudulent conduct and preserve assets for investors.'

On its website CAS said: 'Antigua and Barbuda is a well established and sophisticated offshore financial centre. CAS Hewlett & Co. is there to assist you as an existing or potential offshore investor.

'Our portfolio of clients in the offshore financial sector - past and present - includes banks, insurance companies and various other financial institutions and intermediaries.'

'Marking over 35 years in existence, CAS Hewlett & Co.'s pool of consultants is vastly experienced. Our firm's repute is derived from the high standards we demand of ourselves.'