A team of notorious American internet spammers has been fined a record $230m for bombarding MySpace users with adverts for pornography and gambling websites.

"Spam king" Sanford Wallace, along with his business partner Walter Rines, were yesterday ordered to pay unprecedented damages to the social networking website – amounting to the strongest punishment ever handed out to a spammer in the US.

A court in Los Angeles heard how Wallace and Rines sent more than 700,000 messages to MySpace users, fooling them into visiting gambling sites or adult-rated pages. Disguised as comments from the user's friends, the notes in fact contained advertisements that made the pair a small fee every time somebody was fooled into clicking on them.

Although evidence suggested that the pair made around $500,000 from their activities, district judge Audrey Collins used the terms of America's CAN-SPAM Act – which can levy up to $300 for each infringement of the law.

Wallace has long been one of the world's most high-profile junk marketers, earning the nickname "Spamford" for his recurring trouble with the law. In the early 1990s he progressed from circulating fax messages to sending internet spam – and rose to prominence as the head of infamous Philadelphia-based spam giant Cyber Promotions.

The duo, who failed to turn up at court for the judgment, were also banned from similar activities in the future – though experts said it may not deter them.

"These two spammers are just the tip of an iceberg," said Graham Cluley, senior technology consultant for internet security company Sophos. "Even if MySpace were to extricate the fine from these two men – which seems unlikely given their past record – there will be plenty more cybercriminals trying to make money from junk email."

The $230m fine is many times greater than previous records for such activities, and is almost half of the $580m paid by Rupert Murdoch's News Corporation for MySpace itself in 2005. Hemanshu Nigam, the website's chief security officer, said the company would continue suing spammers who abused its systems.

"MySpace has zero tolerance for those who attempt to act illegally on our site," Nigam said. "We remain committed to punishing those who violate the law and try to harm our members."