Self-proclaimed "Spam King" Sanford Wallace, a Las Vegas man who is accused of breaking into Facebook accounts and sending more than 27 million spam messages to Facebook users, may face imprisonment for more than 16 years, along with a fine of $2 million.

Wallace, 43, is said to have compromised about 500,000 Facebook accounts between November 2008 and March 2009, according to the Justice Department. He allegedly used phishing attacks to steal usernames and passwords and then posted the spam on the users' wall in the social networking site. Whoever clicked on the link was redirected to the websites of affiliate marketing companies, who paid Wallace for pulling Internet traffic for their sites.

However, Wallace pleaded not guilty during an initial court appearance on Thursday. According to an indictment filed on July 6, Wallace was charged with six counts of electronic mail fraud, three counts of intentional damage to a protected computer and two counts of criminal contempt. The charges against him were made public on Thursday after he turned himself in to federal authorities.

Wallace has a history of spamming. Back in 1990, he gained fame as one of spam's most vocal defenders. In the 1990s, he headed a company called Cyber Promotions that used to send about 30 million junk e-mails a day, CBCNews reported.

Because of his activities, Wallace faced a number of civil actions that include court cases from social networking site MySpace in 2008 and U.S. Federal Trade Commission in 2006.

In the 2008 lawsuit, MySpace won a $230 million judgment against Wallace and his partner, Walter Rines over junk messages sent to its members. Moreover, a fine of $4 million was imposed on Wallace in 2006 as the Federal Trade Commission accused him of running an operation that tainted computers with spyware.

In 2009, Facebook sued Wallace under federal anti-spam laws known as CAN-SPAM and won a $711 million civil judgement against him. As par the judgement, Wallace was banned from using the social networking site, but he had violated the judgement within a month.

According to the criminal indictment, Wallace allegedly logged into Facebook during an April 2009 Virgin Airlines flight from Las Vegas to New York. In January this year, he also allegedly created a Facebook profile under the user name David Sinful-Saturdays Fredericks.

"Now Wallace also faces serious jail time for this illegal conduct. We will continue to pursue and support both civil and criminal consequences for spammers or others who attempt to harm Facebook or the people who use our service," Chris Sonderby, Facebook's lead security and investigations counsel, said in a statement.

Wallace was released on Thursday after he posted a $100,000 unsecured bond. His next court appearance is scheduled for Aug. 22 at the U.S. District Court for the Northern District of California in San Jose, Calif. Wallace was ordered not to access social networking sites like Facebook and MySpace. 

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