November 1, 2021: A 24-year-old man dressed as Batman's Joker costume went on a stabbing spree on a Tokyo train line on Sunday evening, injuring 17 people as many party-goers headed into the city centre for Halloween gatherings, according to reports.

The Police have reportedly arrested the attacker on the spot.  A man believed to be in his 60s was unconscious and in critical condition after being stabbed, while witnesses also said the attacker had spread fluid around the train and started a fire, according to reports.

A viral video on Twitter showed a steady stream of people running away from a train car where, seconds later, a blaze lit up, while another footage of the incident showed passengers rushing to squeeze out of the train's windows and onto the platform where the train had made an emergency stop.

The attack occurred on the Keio express line bound for Shinjuku, the world's busiest rail station, at around 8 p.m. (1100 GMT), reports said.