Five people have been injured, three of them critically, in a stabbing on board a bus in the western German city of Siegen, police said on Friday evening. A 32-year-old female suspect has been arrested, police said. Another person suffered serious injuries, it said. At least 40 people were on the bus travelling to a city festival in Siegen, located some 75 kilometres east of Cologne, when the attack occurred at around 7:40 pm (1740 GMT), according to the statement. The incident comes exactly one week after the fatal stabbing in the western German city of Solingen, where a knife-wielding attack…