AM100 retailer Holdcroft Motor Group is recovering from a cyber attack which reportedly left some of its core systems "damaged beyond repair".
Staffordshire Police and the Information Commissioner's Office (ICO) are investigating the attack, which Holddcroft's staff were warned has resulted from the loss of data from internal storage areas and "some of the data that has been compromised may contain employee personal data".
It was a ransomware attack accompanied by demands for a significant payment
"This is a significant attack that should be taken extremely seriously and we are working very closely with both Staffordshire Police and the National Cyber Operational Unit to trace how this has happened," Holdcroft told employees.
"We have now managed to resolve the majority of access issues that employees have been experiencing, although some of our core systems have been damaged beyond repair or have been permanently deleted."
After the cyber attack on July 27, Holdcroft's dealer management system which holds customer data remained unaffected, and operations director Chris Greenhall told the Stoke Sentinel newspaper that the group thanked the efforts of all its people and suppliers "who worked tirelessly to limit the disruption to our ongoing activities".
Holdcroft is now warning staff against accessing personal sites from their office computer and has urged them to change their passwords for any personal accounts such as emails, banking and pensions.
Employees are also being encouraged to 'remain vigilant' over the coming weeks and report any suspicious activity to the company's IT department.
Ransomware attacks were highlighted by the DMS firm Dragon2000 in 2017 as a threat to motor retailers.