A Chicago-area woman who criticized her landlord on Twitter is facing a $50,000 defamation suit.

Horizon Group Management sued the woman, identified as Amanda Bonnen, on Monday in Cook County Circuit Court, the Chicago Sun-Times reported Tuesday. The company, which claims to manage 1,500 apartments in Chicago, says it was "maliciously and wrongfully" defamed by the defendant's tweet. The person posting the message went by the Twitter name "abonnen."

A member of the family that has run Horizon for 25 years told the Sun-Times the company did not ask the woman to take down the post. "We're a sue first, ask questions later kind of an organization," Jeffrey Michael told the newspaper. On Tuesday, many Twitter users voiced support for Bonnen. A few suggested setting up a legal defense fund and many re-posted abonnen's original comment.

While it's unusual for tweets, which have a maximum of 140 characters, to spark legal action, libel suits are not uncommon on the Web. This month, the British High Court ruled that Google wasn't liable for defamatory content found through its search engine.

Also, Metropolitan International Schools, a U.K.-based online training company, objected comments in Internet forums that disparaged the company.

In January, model Liskula Cohen sued Google to force the company to reveal the people responsible for an allegedly defamatory blog called Skanks in NYC that the company's Blogger service hosts.

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