A man was pronounced dead after he was discovered in a busy street close to Sunderland city centre.
Police and paramedics were called to New Durham Road, close to the University Metro station, at 12.50am on Saturday after the man, aged in his 40s, was found.
A spokeswoman for Northumbria Police said: "Police received a report of concerns for a man in New Durham Road outside Sunderland University Metro station.
"The man was pronounced dead at the scene.
"There's believed to be not third party involvement and a report is being prepared for the coroner."
Police have said they know the identity of the man, but his details have not been released.
The North East Ambulance Service sent an ambulance, first responder and a ground team attached to the air ambulance service to the scene.