Popular Irish internet forum boards.ie has reported an attack on its user database which could affect thousands of users. In a statement, it confirmed that 'an unauthorised source' accessed its database server this morning.

'Part of the database which includes our members' usernames, email addresses and obfuscated passwords was accessed,' the statement said.

A sister site, Adverts.ie, was also affected. The Daft media group has a minority stake in Boards.ie.

Boards.ie has asked all members who use the same username/email and password on other sites to change passwords as a precaution.

'Like all large sites we are regularly the target for disruption and take continual actions to proactively protect your data,' the statement said.

'This particular attack was completely unprecedented despite our rigourous security measures and while we have no idea if this data will be used for any malicious reasons, we felt it vital to tell you this immediately,' it added.