 A man has been left in a critical condition after a knife and arson attack on an underground train line in the Japanese capital, Tokyo. At least 10 others were also injured in the incident. Passengers ran for their lives, some climbing out of the windows as fire raged in a carriage on the train. The suspected attacker, who is a man in his 20s, was arrested at the scene. Eyewitness reports say the suspect sprayed a clear liquid around the carriage before setting it alight.