Payroll details of 100,000 Morrisons staff including bank account numbers leaked by insider and published on the web

Company insider 'downloaded payroll details and posted them online'

Firm has launched an investigation and vowed to support employees if they are targeted by fraudsters

Leak comes one day after Morrisons announced a £167million annual loss



Morrisons staff are feared to be at risk from fraudsters after their bank account details were stolen and published online, it emerged today.



The firm launched an investigation after information about 100,000 employees was apparently leaked by an insider and posted on the internet.



The blow comes just one day after the supermarket chain announced that it made a loss of £176million and pledged to cut prices to compete with Aldi and Lidl.



Leak: The man was arrested in Leeds - close to the supermarket's headquarters in Bradford - earlier this morning following the theft of payroll information from a central database

The leak came to light when a member of the public downloaded the data onto a CD and sent it to a local newspaper.



In a letter to employees, Morrisons said: 'We are extremely sorry to inform you that there has been a theft of colleagues' personal information, which was uploaded onto a website.

'As soon as we became aware of this last night we took immediate steps to ensure the data was removed from the website. It was closed down within hours of us being notified.

'The information included names, addresses and bank account details of colleagues. This affects colleagues from all levels of the organisation.'

Probe: Chief executive Dalton Philips is heading the company's investigation into the hack

The company has set up a hotline and dedicated email address for staff who are worried about the possibility of their information falling into the hands of scammers.

The investigation into the leak, which was apparently carried out by an insider with access to the payroll rather than a hacker, will be carried out by chief executive Dalton Philips.

British banks have been warned of the possibility of hackers accessing accounts, while consultants have been brought in to advise workers how to keep themselves safe.



Morrisons added in a statement: 'This data theft included bank account details. Initial investigations suggest this theft was not the result of an external penetration of our systems.



'We can confirm there has been no loss of customer data and no colleague will be left financially disadvantaged.



'We have already informed our colleagues about the theft and we are helping them take the appropriate actions to safeguard their personal data.'

Employees took to social media today to vent their anger at the company - with many criticising Morrisons for announcing the news on Facebook before all staff had been personally informed.



One wrote: 'A hack? So why weren't these details encrypted and what not?'



Another added: 'Reading about this on Facebook does not inspire confidence, we should have been notified by phone by our HR departments first thing this morning.'



The leak was revealed by the Telegraph and Argus, a newspaper based in Morrisons' home town of Bradford, after 'a concerned Morrisons shopper' sent the data to it.

It is not known for how long the information was available.

A spokesman for West Yorkshire Police said: 'We are aware of the situation and are supporting Morrisons in their investigation into these matters.'

A spokesman for the Information Commissioner said: 'We have been made aware of reports that Morrisons have suffered a potential data breach, and we will be making enquiries.'



Yesterday the company, which is Britain's fourth biggest supermarket, revealed that it lost £176million last year thanks to a combination of falling sales and one-off costs.