London, Aug 24: An unknown Indian hacker is being charged with the greatest cyber-heist in history for allegedly helping a criminal gang steal identities of an estimated eight million people in a hacking raid that could ultimately net more than 2.8 billion in illegal funds.

An investigation by Scotland's Sunday Herald newspaper has discovered that late on Thursday night a previously unknown Indian hacker successfully breached the IT defences of UK's Best Western Hotel group's online booking system and sold details of how to access it through an underground network operated by the Russian mafia.

There are no details yet on how the hacker was identified to be an Indian and if a probe is on to identify the person. It is also not known if the hotel chain has alerted the police about the heist.

The attack scooped up the personal details of every single customer that has booked into one of Best Western's 1312 continental hotels since 2007. Amounting to a complete identity-theft kit, the stolen data includes a range of private information including home addresses, telephone numbers, credit card details and place of employment.

"They've pulled off a masterstroke here," said security expert Jacques Erasmus, an ex-hacker who now works for the computer security firm Prevx. "There are plenty of hacked company databases for sale online but the sheer volume and quality of the information that's been stolen in the Best Western raid makes this particularly rare. The Russian gangs who specialise in this kind of work will have been exploiting the information from the moment it became available late on Thursday night. In the wrong hands, there's enough data there to spark a major European crime wave."