Train staff were left shocked after realising a man they thought was sleeping was actually dead at the end of a five-hour journey.The passenger, described as being 'elderly', boarded a service from Manchester Piccadilly to Bournemouth on Saturday May 30, according to the Manchester Evening News.As rail workers passed him in his seat, they thought he was having a nap during his journey.But when the service arrived at its destination, he had not yet left the carriage.Emergency services were called, but sadly there was nothing that could be done and he was pronounced dead at the scene.It is not known at what point in the journey the passenger died.British Transport Police (BTP) said the man's death was caused by a 'medical matter'.His family.