The world celebrated the fifth annual International pillow Fight Day with massive pillow fights, as people from 115 cities across the world took joyfully to the streets for a day of fun and frolic. It almost looked like a war zone, until a closer look revealed the grins on the participants' faces!

There was a large group having all the fun they could, outside Berlin's famous Brandenburg Gate, in Germany. There were also groups of pillow fighters at the National Gallery, in Trafalgar Square, as also in Birmingham and Liverpool, all of which were promoted through social media.

Unfortunately, the police in China failed to get the joke and the mob in Shanghai had to lay down "arms" for a few minutes, while the authorities were informed of the occasion and allowed the "fight" to begin.

Equally unfortunately, the climate in Russia played spoilsport and people in Moscow and Ekaterinburg may not have been able to pillow fight as much as they would have liked to. The fights were rampant in Taiwan also and everyone agreed it was a great way to de-stress!

"I am so happy that I finally got to release all my stress today, There is a lot of pressure on me from my academic work, problems in my relationship and arguments with friends," 16 year old Taiwanese student Jain Shin-Yu said to Sky News. Shin-Yu was part of a 100-strong contingent who enjoyed the day.

Fortunately, just to ensure there are no injuries, there are rules in place. For one, only soft pillows are allowed and they should be swung only lightly. Furthermore, it is forbidden to swing at anyone without a pillow or anyone holding a camera.

The event, which started off as a flash mob routine, is promoted by the Urban Playground Movement, which organises such free all-ages public agents. However, the company's Web site offers no explanation as to why people might actually want to pillow fight in the streets. The organisers discourage pillow fights in parks, not only due to littering concerns but because apparently "most events in parks are boring".

Meanwhile, the largest pillow fight in the world, according to the Guinness World Records, took place iat Minehead Butlins, in Somerset, on 14 November, 2008. The event was part of the BBC's Children in Need night and the fight raised over £3,000 and saw 3,706 participants.

Check out photos of pillow fights from across the world...