The attack is specific to the pan-European book specialist’s UK business, which operates from eight sites.

Divisional managing director Tanya Dunbar told Printweek the attack had taken place in the early hours of 7 February, and the hackers had disabled the firm's IT systems.  

“After completing initial forensic analysis we were able to determine that we had encountered a cyber attack, this despite having significant protection already in place across our entire network,” she said.

“As soon as the attack was identified, we engaged specialist external technical support, who along with our own teams have been working to recover our systems as quickly as possible.”

She said significant progress had been made in restoring the systems.

“Our colleagues across the whole business have been working extraordinarily hard to develop workarounds as well as to reimplement our IT systems and have made substantial progress.

“We continue dialogue with our customers and other stakeholders to ensure that they are fully aware of the status. We expect to resume full services gradually over the coming days.”

Dunbar did not disclose how the cyber attackers had accessed the firm's systems.