New Delhi: At least 17 people were reported injured after a fire broke out Sunday night on a Keio Line train in Tokyo, with authorities immediately arresting a man who was carrying a knife, local news reported.

Kyodo News reported, that investigative sources are looking into a report that hydrochloric acid has spread on the train. The police received a report regarding a knife-wielding man around 8 pm. The incident took place on a 10-car train bound for Shinjuku in central Tokyo.

The incident took place on world’s busiest – Keio express line bound for Shinjuku station on Sunday, while people were headed to Tokyo for Halloween parties.

As per the reports, the attacker was wearing a green shirt, a blue suit and a purple coat like the Joker in the Batman comics. He reportedly spread fluid in the train before igniting it.

京王線火災（テロ？）規制線が貼られました pic.twitter.com/TJDkIef0EO

— しずくβ (@siz33) October 31, 2021

Witness claimed they saw the attacker walking his way while slowly waving a long knife smeared with blood. “I thought it was a Halloween stunt,” a witness told the Yomiuri newspaper.

“Train doors were closed and we had no idea what was happening, and we jumped from the windows. It was horrifying”, witness Shunsuke Kimura said.

A similar attack took place in August this year, a day before the Tokyo Olympics closing ceremony, when a 36-year-old man had stabbed more than 10 passengers on a commuter train.

The man later told police that he wanted to stab any women who looked happy.