Police are appealing for information and witnesses following the death of a man in Radlett.
Police were called by the ambulance service at 4.53am on Sunday (22 May) to a house in Theobald Street.
The man had been taken out of a swimming pool was unresponsive and he was sadly pronounced dead.
The family of the man, who was aged in his twenties, are being supported by specially trained officers.
The Bedfordshire, Cambridgeshire and Hertfordshire Major Crime Unit are investigating the circumstances of his death.
Detective Inspector Iain MacPherson, from the BCH Major Crime Unit, said: “Firstly my thoughts are with the man’s family and friends at this very difficult time.
“We are trying to piece together what happened and I would like to appeal for the public’s help. There was a party happening in the house at the time and although we’ve spoken to a number of attendees, we believe there are others who left the party early but could still have information that will help our investigation.
“Please get in touch if you think you might be able to help. The man’s family need to understand what happened.”