A 42-year-old man has died at a flat fire in Midlothian.Fire crews and police were called to a property in the Mayfield area of Dalkeith at about 01:45.The man was taken from the building in Hawthorn Crescent but was pronounced dead at the scene.Lothian and Borders Police said an investigation was under way to establish the cause of the blaze. The name of the victim will not be released until next-of-kin have been informed.