Check out this pillow fight...

Now you may not have heard of International Pillow Fight Day but thousands of people across the world took part in it on Saturday!

There were pillow fights across America, as well as in Toronto in Canada and Hong Kong.

Crowds even gathered in London's Trafalgar Square to hit each other about the head.

The organisers said they wanted to encourage people to socialise more and spend less time watching TV.

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