An air passenger was arrested under the Terrorism Act and held in a police cell for seven hours after joking on Twitter he would blow an airport 'sky high' if his flight was delayed.
Paul Chambers, 26, posted the message after snowfall threatened to delay his plans to travel from Doncaster's Robin Hood airport to Ireland on January 15.
The finance supervisor wrote: 'C***! Robin Hood airport is closed.
'You've got a week and a bit to get your s*** together, otherwise I'm blowing the airport sky high"
Police were alerted and Mr Chambers was arrested.
He was held under the Terrorism Act on suspicion of conspiring to create a bomb hoax and questioned for seven hours.
Mr Chambers was eventually released on bail until February 11 pending further enquiries.
His Twitter post was deleted and his laptop, iPhone and home computer confiscated.
He also been banned from Robin Hood airport for life and suspended from his job while an internal investigation is launched.
'My first thought on seeing the police was that perhaps a member of my family had been in an accident,' he said.
"Then they said I was being arrested under the Terrorism Act and produced a piece of paper.
'It was a print-out of my Twitter page. That was when it dawned on me.
"I had to explain Twitter to them in its entirety because they'd never heard of it.
'Then they asked all about my home life, and how work was going, and other personal things,' he said.
'The lead investigator kept asking, "Do you understand why this is happening?" and saying, "It is the world we live in".
'I would never have thought, in a thousand years, that any of this would have happened because of a Twitter post.
'I'm the most mild-mannered guy you could imagine.'
Civil liberties campaigner Tessa Mayes said: 'Making jokes about terrorism is considered a thought crime, mistakenly seen as a real act of harm or intention to commit harm.
'The police's actions seem laughable and suggest desperation in their efforts to combat terrorism, yet they have serious repercussions for all of us. In a democracy, our right to say what we please to each other should be non-negotiable, even on Twitter.'
A spokesman for South Yorkshire Police said: 'A male was arrested on 13 January for comments made on a social networking site. He has been bailed pending further investigations.'
Mr Chambers is thought to be the first person in this country to have been arrested for comments on Twitter, although cases have been reported in the United States.