Twitter users, take heed: The Department of Homeland Security doesn’t find your “Family Guy” jokes very funny. Especially if it sounds like you’re planning something illegal for your holiday.

The novel “1984,” whose term “thoughtcrime” is being applied to battles of free speech on Twitter. (Brown University Library/Fair Use)

The Sun reports that Leigh Van Bryan, 26, who wrote the offending tweets, and his friend Emily Bunting, 24, were detained by Homeland Security on arrival in L.A., questioned for five hours, handcuffed, put in a van with illegal immigrants, and then held overnight.

While they were detained, Bryan and Bunting tried to assure U.S. officials that they were simply joking, arguing that “destroying” was a word that simply means partying in Britain. “We just wanted to have a good time on holiday. That was all Leigh meant in his tweets,” Bunting told the Sun.

The two were sent packing anyway.

Bryan’s tweets are now set to private.

The Next Web points out that Twitter users have been increasingly taken to task by officials for tweets, including a high profile case of a British man’s off-color joke about bad weather closing the airport.

“Robin Hood airport is closed. You’ve got a week to get your [expletive] together, otherwise I’m blowing the airport sky high!!” Paul Chambers wrote on Twitter in 2010. Chambers was arrested on terrorism charges for the tweet and found guilty of sending a “grossly offensive” message “by a public communications network.” Chambers also lost his job twice as a result.

At the time, many Twitter users decried the consequences Chambers had faced, rallying their support for him around the hashtag #twitterjoketrial.

“Thoughtcrime” is a term from George Orwell's dystopian novel “1984,” in which simply thinking could land a person in prison.

In January 2010, Birgitta Jónsdóttir, a member of the Icelandic Parliament, was notified by Twitter that the company had been served a subpoena by the U.S. Department of Justice demanding information about her tweets. The tweets DOJ was interested in are believed to be several ones Jónsdóttir wrote about WikiLeaks, where she has worked as a volunteer.

On her blog, Jónsdóttir recently wrote a post entitled “My Twitter Case and ‘Thoughtcrime,’” warning webizens:

Many users do not understand that they are giving away all control of their web usage... Personal data can be used against you...!This is very dangerous to those, like me, who are activists, journalists and researchers. It equally endangers the merely curious.

Jónsdóttir is now campaigning against the ability of officials to prosecute people for their public written communications, especially on Twitter.