South Korean authorities have introduced a new online identity system in an attempt to combat a wave of identity theft that affected more than one million people earlier this year.

Citizens will now be able to apply for a special Internet Personal Identification Number, or i-PIN, the country's Ministry of Information and Communication announced this week. 

Koreans commonly use their 13-digit citizen registration numbers to verify their identities online. However, due to lax security at internet firms, databases containing these numbers have fallen into the hands of criminals.

The numbers have also come under fire because they contain personal information which the holder may not wish to divulge online, including gender, and place and date of birth.

The new i-PIN numbers do not contain any personal data. In addition, under the new system, citizens will be able to cancel their old i-PIN number and apply for a new one if they suspect that the number has been copied.

Earlier this year, some 1.2 million people, more than two per cent of the country's population, found that their official citizen registration numbers had been used to sign up for accounts in Lineage, a series of popular online games. 

Although there were earlier cases of existing Lineage accounts being hijacked, the victims in the vast majority of recent cases did not even play the game. Instead, their real-world identities were used to sign up without their knowledge.