The company behind one of the world's most successful online games has filed criminal charges against its founder, accusing him of pocketing millions of dollars of company revenue.

Nasdaq-listed Gravity Corporation, the Korean developer of Ragnarok Online, which claims millions of subscribers worldwide, claimed yesterday that Jung-Ryool Kim had siphoned off more than $9.1m from its coffers over the past three years. 

Kim, who picked up $380m last year by selling his stake in the company, has already repaid some of the missing money.

Gravity will revise its financial statements for 2002 to 2005 to include the missing income, the company said, and may face additional tax charges or even civil penalties as a result.

Prior to that restatement, the company reported revenue of about $101m in 2004, the most recent period for which it provides data. 

Founded in 2000 with $500,000 of Kim's cash, Gravity enjoyed a meteoric rise. Its signature game, Ragnarok Online, claimed over 700,000 simultaneous players in 65 countries worldwide during peak hours. 

There are over 33 million Ragnarok accounts registered, according to media reports, although it is unclear how many of these are currently in use.

Ragnarok is a massively multiplayer role-playing game set in a fantasy world based loosely on a popular Korean comic book of the same title. It began life as a free game in 2001.