Tokyo commuter Katsuo Katugoru caused havoc on a crowded tube train when his inflatable underpants unexpectedly went off.

The rubber underwear was made by Katsuo himself, and designed to inflate to 30 times their original size in the event of a tidal wave. "I am terrified of water, and death by drowning is my greatest fear" said Katsuo, 48. "Unfortunately I set them off accidentally while looking for a boiled sweet on a rush hour train. They were crushing everybody in the carriage until a passenger stabbed them with a pencil."