By Benedict Tetzlaff-Deas Shocking new pictures show a man armed with a massive blade after a passenger wasstabbed on a busy train. Police said they were making urgent efforts to trace a man who carried out the knife attack on a train near Beckenham Junction, London which left one man with serious injuries. Footage shared online showed a man in a hood lunging at another who was sat down as fellow passengers cried out in shock. The incident took place shortly after two men boarded the train at Shortlands railway station. Another clip later showed a man walking down the street with a knife. No a…