Japan's rowdy, cosplay-themed Halloween celebrations have become famous around the world, with young people congregating in city hot spots and theme parks where they snap selfies in outrageous outfits and ghoulish get-ups.

In recent years, thousands of revelers — dressed up in supergraphic costumes to look like such characters as sexy zombies, stabbing victims and even the eccentric animal skin-clad viral star Pikotaro — have been drawn to the giant street party that takes place on Shibuya's famous scramble crossing, making movement there nearly impossible.

"From about four years ago, people started going out on the streets rather than enjoying Halloween events in clubs or bars," Shibuya Ward Mayor Ken Hasebe said at a recent news conference ahead of the Oct. 31 annual celebration.