The San-Francisco-based microblogging site Twitter, which became the target of a prolific Internet worm, was hit aggressively in a four-attack series over the weekend - beginning Saturday morning and continuing till early Monday morning. Essentially a computer program designed for proliferation, with the aim to infect users over a network and alter profile pages, the worm reportedly compromised thousands of accounts.

In a company blog, Twitter co-founder Biz Stone confirmed that the attackers initially created four accounts to allow the worm to spread speedily over the Twitter site early Saturday morning. Stone added that Twitter's security team was pressed into service later that morning, but not before 90 accounts had been compromised by 11 a. m.

Stone said that the second "much more intense" round of attacks by the malicious worm began Saturday afternoon, increasing the number of the compromised accounts to nearly 100. Later, in two fresh attacks, the worm hit Twitter users on Sunday and Monday morning. Stone says that the worm has apparently not acquired passwords, phone numbers or "other sensitive information" mostly used for identity-theft attacks.

Interestingly, the Saturday worm was released by 17-year-old StalkDaily creator, Michael Mooney, from Brooklyn, New York. Saying that he "did this out of boredom", Mooney told BNONews. com that the reason behind the attack was to expose Twitter's weaknesses and publicize his own site!