The popular online social networking Web site MySpace.com has sued a Colorado man once accused of being one of the world's top three spammers, saying the man gained access to MySpace profiles using stolen passwords and used the information to send spam bulletins.

MySpace, which is owned by News Corp., claims Scott Richter and his various companies, including OptInRealBig.com and Mediabreakway.com, sent millions of spam messages to members using technology that made the messages look like they had come from individual members' accounts.

The lawsuit was filed Friday in U.S. District Court in Los Angeles and asks for damages, an injunction preventing Richter and his companies from accessing MySpace, and repayment of all profits gained as a result of the activity.

Several calls to Richter were not returned Monday.

Managing its rapid growth has been a challenge for MySpace, which has fallen prey to people who launch spam attacks.

Unlike random unsolicited e-mails, which are readily identified as junk, the spam bulletins on MySpace appear to be sent by trusted friends, giving them an air of legitimacy.