The accountancy watchdog has started a probe into the audit by EY of the financial statements of Thomas Cook for the year ended last September.
The investigation will be conducted by the Financial Reporting Council’s enforcement division under its audit enforcement procedure.
The FRC said it will “keep under close review both the scope of this investigation and the question of whether to open any other investigation in relation to Thomas Cook, liaising with other relevant regulators to the fullest extent permissible”.
The disclosure came as the Civil Aviation Authority revealed that it has now returned three quarters of the 150,000 Thomas Cook holidaymakers due to fly back to the UK between its collapse last Monday and October 6.
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Some 115,000 holidaymakers have now been flown back to UK in the first eight days of the Operation Matterhorn repatriation exercise.
The CAA said 7,000 people are due to fly back today (Tuesday) on 39 flights.
The aviation regulator’s chief executive Richard Moriarty said: “As we start the second week of our flying programme, we remain firmly focused on the enormity of the challenge we still have to deliver.
“We have returned over three quarters of Thomas Cook passengers back to the UK and are now also working on the challenge of refunding the 360,000 Atol protected future bookings as soon as possible.
“The scale and complexity of our repatriation and refund operations will inevitably cause some inconvenience and disruption and I would like to thank Thomas Cook customers for bearing with us.
“For those customers that are still abroad, we have set up an online form to provide us with contact information. Please fill out this form as we may need to contact you about your flight.”
The form is available on a dedicated website
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