Mr Michael Barrymore has been arrested over the death of a man found in the swimming pool at his home.
Police say two other men are being questioned at Harlow police station by officers from Essex police's major investigations team.
Mr Barrymore(49), from Roydon, Essex, is being questioned about alleged drugs offences. The two younger men are being held on suspicion of murder.
Mr Barrymore was seen arriving at Harlow police station shortly before 9am. Witnesses said the comedian arrived in an unmarked car and said nothing to waiting journalists.
The police spokesman said a 49-year-old man from Roydon, Essex, had been arrested on suspicion of various drugs offences.
The spokesman said a 31-year-old man, from Blackpool, Lancashire, and a 26-year-old man from Harlow had been arrested on suspicion of murder.
Butchery worker Mr Stuart Lubbock (31) from Harlow, was found unconscious in a swimming pool at Mr Barrymore's home in Roydon, near Harlow in late March. He died in hospital shortly after being discovered.
The police spokesman refused to confirm or deny whether the 49-year-old man being questioned was Mr Barrymore.
The spokesman said the man had been arrested on suspicion of possessing Class A and Class B drugs and allowing premises to be used for drug-taking.
PA