Emergency services were called to Runhead Terrace, Ryton, in Gateshead, on Saturday, after a 46-year-old man was found dead at home.
A uniformed officer stood guard outside the terraced property as forensic officers in white suits combed the property for clues and took photos.
The man, named locally as Paul Hebden, is understood to have lived alone for many years and was made redundant from his job as a postman last year. The coroner has been informed and an inquest will be opened shortly. Anyone with information can call 0345 604 3043.