Feathery fisticuffs: Thousands of revellers across the world get involved in World Pillow Fight Day
World Pillow Fight Day took place everywhere from Amsterdam to ZurichTrafalgar Square was overtaken by a pillow flashmob for an hourThere were two rules: Don't hit anyone with a camera or without a pillow
20:47 GMT, 6 April 2013
04:02 GMT, 7 April 2013
A pillow-wielding mob descended on Trafalgar Square today for feathery fisticuffs in front of London's most iconic monuments.
Trafalgar Square's usual inhabitants – tourists and pigeons – beat a hasty retreat as a flashmob of thousands gathered for a good old-fashioned pillow fight in the sunshine.
Similar scenes were repeated all over the world as part of annual World Pillow Fight Day.
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No escape: Trafalgar Square was crammed full of revellers whacking each other in one of the first warm days of the year
Feathery fracas: Revellers took part in a giant pillow fight in London on 'International Pillow Fight Day' on Saturday afternoon
New York: People hit each other with pillows as they take part in the world's 6th annual Pillow Fight Day in Washington Square Park
People participate in International Pillow Fight Day at Washington Square Park in New York April 6
Huge crowd: Londoners prepared for an epic fight in the sunshine with the National Portrait Gallery in the background
For the fifth year in a row, Trafalgar Square was invaded for an hour of relaxation in the sunshine as Londoners let their inhibitions go and attacked strangers with gusto.
Equally enthusiastic scenes were replicated in major U.S. cities including Atlanta, Boston and Chicago and as far afield as Hong Kong.
There were just two rules.
Revellers were not allowed to hit anyone with a camera, or anyone not armed with a pillow.
Thrashing it out: The scenes in London were replicated in major cities all over the world
A sign of spring: An Easter bunny dropped in for a good natured tussle
Feathery fun: Londoners let their hair down and their inhibitions go as they seemed to have entirely scared off the resident pigeons
Sea of feathers: One particularly enthusiastic girl got heavily involved in the action