The UK Attorney General. (Credit: Dominic Grieve's website, screenshot)

UK Attorney General Dominic Grieve “warned” UK tweeters about potential libel cases over tweets, Agence France-Presse reported.

Grieve noted that even anonymous tweeters don’t have “immunity” and that “if I think it is necessary to prevent crime, such as racially aggravated harassment, then I won’t hesitate to” bring cases against tweeters.

The Telegraph listed a few cases recently that have prompted legal action, including:

• the jailing of a student for a “racially aggravated public order offence” for a tweet that “mocked Bolton FC football star Fabrice Muamba on Twitter after he collapsed with a heart attack”
• community service for a blogger calling for “excrement through a local councillor’s letterbox” and
• arrests for “the alleged naming on Twitter of the victim” in a rape case.

We wrote in March about the first Twitter libel ruling, in which Indian Premier League founder Lalit Modi was ordered to pay retired cricket player Chris Cairns about £490,000 for tweets accusing Cairns of “match-fixing.”