Police have discovered the bodies of a man and woman who had been shot in the head.
Officers from Durham Constabulary were called to Crook Golf Club in Durham where they found the pair in a car.
The force is not looking for anyone else in the investigation, it said.
Acting Detective Superintendent Kevin Weir said: "We are carrying out a full investigation to establish the identities of the people in the vehicle and the events leading up to their deaths.
"Although enquiries are at their very early stages I must reassure people that we do not believe the wider community is at any risk at this time."
Police were called to the scene on Low Job's Hill, Crook, at 11.35am "acting on information received", a spokeswoman said.
The pair, who police said were believed to be a man and woman, were thought to have sustained "serious gunshot wounds to the head".
The spokeswoman said: "The area has been cordoned off and a full investigation is being carried out".