Bad Santas! Chaos as thousands of revellers dressed as Father Christmas descend on London for huge pub crawl

The annual event is a flash mob style celebration that started in 2000 and has gained popularity through social networking websites. As well as in London, the revelry now takes place in about 300 cities around the world, including New York, Vancouver and Moscow. The first SantaCon took place in San Francisco in 1994. The New York parade is said to be the largest with around 30,000 Santas taking part.