Tokyo police are warning Halloween revelers to be on the alert for pickpockets in the Shibuya district.
Police say pickpockets are increasingly active in the area around the station. A 24-year-old man was arrested on Saturday for allegedly stealing a wallet and a cellphone from a woman's bag.
Police have mobilized hundreds of officers to deal with any possible disorder. A number of incidents of vandalism and other criminal activity occurred during last year's Halloween season.
Shibuya Ward has banned drinking on the streets and in parks near the station from 6 p.m. on Thursday to 5 a.m. on Friday.