The unauthorised access to systems from May 31 to Nov. 4, 2017 was gained from a single and isolated user account. The third party copied data and demanded a ransom for its safe return, the company said.

Potential user information compromised may include dates of birth, addresses, bank account information and passport and payment card information, the company added.

Clarkson did not say how many individuals were affected by the hack, but said that through investigation and legal measures, it was able to trace and recover copies of the data.

(Reporting by Rama Venkat Raman in Bengaluru; Editing by Peter Cooney)