The Government’s most senior law officer has warned users of Twitter and other social media sites not to believe the internet was law-free.

Due to a slew of high-profile court cases involving postings made on the micro-blogging site Twitter, Attorney General Dominic Grieve decided to issue a caution.

Mr Grieve told BBC Radio 1′s Newsbeat: “If somebody goes down to the pub with printed sheets of paper and hands it out, that’s no different than if somebody goes and does a tweet.

“The idea that you have immunity because you’re an anonymous tweeter is a big mistake.”

He went on: “I don’t want to take action but if I think it is necessary to prevent crime, such as racially aggravated harassment, then I won’t hesitate to do it.”

So what has happened to lead to this warning?

• A student who mocked football star Fabrice Muamba on Twitter after he collapsed with a heart attack was jailed for 56 days after admitting a racially aggravated public order offence

• A message by a blogger who invited followers to put excrement through a local councillor’s letterbox, led to a community sentence of 80 hours of unpaid work.

• 17 arrests have been made in connection with the alleged naming on Twitter of the victim in footballer Ched Evans’s rape case.