Yesterday was 'no pants' day on London Underground

The prank started in New York in 2002

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While millions of London Underground passengers face travel chaos today, Tube travellers were given an eyeful yesterday - when fellow commuters got on board wearing no trousers.

People dressed appropriately for the weather above the waist, sporting hats, scarves and coats.

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But below the equator they had nothing their pants on, as part of annual No Pants Subway Ride 2017.

The event originally began in the United States, where trousers are rather misleadingly called 'pants'.

Credits: Dinendra Haria/WENN.com

Dinendra Haria/WENN.com

Credits: Dinendra Haria/WENN.com

Dinendra Haria/WENN.com

What began as a prank by a handful of people on New York City's mass transit system in 2002 has grown into an international celebration of silliness.

Yesterday, dozens of cities around the world participating each year.

Credits: Dinendra Haria/WENN.com

Dinendra Haria/WENN.com

Credits: Dinendra Haria/WENN.com

Dinendra Haria/WENN.com

The global trend has encouraged commuters in capitals around the world, including Prague, Berlin and New York to show their bare legs.

Credits: FameFlynet

FameFlynet

The idea behind the annual day is simple: Random passengers board a tube train at separate stops in the middle of winter without trousers.

Credits: Dinendra Haria/WENN.com

Dinendra Haria/WENN.com

Credits: FameFlynet

FameFlynet

Participants are supposed to behave as if they don't know each other and act normally, as if there was nothing unusual about their attire.