Staff information including bank account details have been sent on a disc to a newspaper and have also been published online.
It has been estimated that around 100,000 employees of Morrison’s Supermarket have been affected.
The blow happened on the same day that the firm issued a huge profit warning posting its lowest annual profit for five years.
The supermarket chain has ensured that the data has taken off the website
Morrison’s has announced that there has been no loss of customer data. They have also said that staff will not be financially disadvantaged by the theft.
West Yorkshire Police are leading the criminal enquiry.
Initial investigations have confirmed that the theft was not an external penetration of their systems.
They believe that the data was likely to have been leaked by an employee.
A helpline has been set up for any staff affected.
An urgent review is now underway to investigate the firms internal data systems.
