It's a city prank in the Big Apple -- you have to board the subway minus your lower garments!

The tenth annual No Pants Subway Ride was held in New York City on January 9 and made for a comic spectacle as usual.

Organised by comedy group 'Improve Everywhere', participation is simple enough -- all you have to do is ride the subway without any pants on!

Hundreds of members of the general public joined in this year, clothed in shirts, jackets, socks, shoes, hats -- everything but pants. Everyone goes about their daily business as if nothing is unusual about stepping out missing an article of clothing. Needless to say, confusion, amusement and shock are common reactions!

Photograph: Christian Hartmann/Reuters