At least 17 people have been injured in a knife and arson attack on an underground train line in the Japanese capital of Tokyo. Video footage shows passengers running through carriages away from flames and clambering out of train windows. The incident happened at around 20:00 local time (11:00 GMT) near Kokuryo station, in the city’s western suburbs. Police say a man in his 20s was arrested at the scene. Local reports suggest he was in a Halloween costume. Eyewitness reports and footage appears to show a suspect in a bright purple and green suit, similar to the Joker character from the Batman comics. “I thought it was a Halloween stunt,” one witness told the Yomiuri newspaper about the attack. “Then, I saw a man walking this way, slowly waving a long knife.” Eyewitnesses say the suspect sprayed a clear liquid around the carriage before setting it alight.(BBC)…[+]