A man arrested on suspicion of the murder and indecent assault of Stuart Lubbock at the home of entertainer Michael Barrymore has been released under investigation by police.
Mr Lubbock, 31, was found unconscious in the TV presenter's pool in Roydon, Essex, in March 2001 following a party.
The unnamed suspect, aged 50, was arrested in Cheshire on 17 March following "significant new information", Essex Police said.
He was initially released on bail.
On Sunday, Essex Police said: "A 50-year-old man arrested on suspicion of the indecent assault and murder of Stuart Lubbock has been released under investigation while our inquiries continue."
Last month Det Supt Lucy Morris said the investigation had been "extremely lengthy and complex".
"We have never given up on finding out what exactly happened to Stuart and we will not stop in our pursuit of justice for him and for his family and friends," Det Supt Morris said.
Mr Lubbock, a butcher from Harlow, was described by neighbours at the time of his death as a "pleasant, sociable" man.
A post-mortem examination found Mr Lubbock had suffered "horrific" injuries prior to his death, police said.
Alcohol, ecstasy and cocaine were found in his bloodstream.
No-one has ever been charged with any offence in relation to his death.
Mr Barrymore, 68, and two other men were arrested in 2007 on suspicion of sexual assault and murder, but were later released without charge.
The TV personality, who was known for shows including Strike It Lucky, has always denied involvement in the death.
An inquest into Mr Lubbock's death, in 2002, recorded an open verdict.