A man whose body was found on a driveway outside a house died of multiple stab wounds to the neck, police said.
But Thames Valley Police say they are still not sure who the man is or whether he was murdered or took his own life.
The man's body was found in the driveway of a house in Telford Way, in Downley, High Wycombe, at 8am on Saturday.
A post-mortem examination was carried out at Wycombe General Hospital and revealed the man died of haemorrhaging due to multiple stab wounds to his neck.
The man is black, with a slight beard at the point of his chin and is thought to be in his 30s. He was wearing dark grey jogging bottoms and a light coloured fleece top with stripes on the arms. He was also wearing a black beanie hat and white trainers.
A mobile phone was found on the man which police are using to try to establish who he is.
The house was cordoned off as forensic officers worked at the scene.
Detective Chief Inspector Mick Saunders, the senior officer investigating the death, said: "We are still investigating the circumstances surrounding the death and at the moment cannot say for sure whether there was third party involvement in the death or not.
"We still do not know the identity of the man.
"It is crucial to the police investigation surrounding the death that anyone who saw anything suspicious at the time or who has any other information contacts us. Similarly, if you know who the dead man is, we would like to speak to you."
