Gay socialite and event organiser Philip Sallon is recovering in hospital after being assaulted in central London on Saturday morning.
Friends said Mr Sallon, 59, suffered a fractured skull and broken bones in the attack, which took place in Piccadilly.
His cousin Joshua Sallon told PinkNews.co.uk that witnesses reported hearing the attackers shout anti-gay abuse.
He said: “Philip was walking past the Gap store on Piccadilly when someone started on him. Philip told him to leave him alone but the man beat him up and stole his watch.”
A police spokesman said: “Officers from Westminster Serious Violence Team are investigating an assault after a 49-year-old [sic] man was attacked and left unconscious in Piccadilly Circus in the early hours of Saturday April 2nd.
“The victim was outside the Gap store at approximately 03:30am when officers believe he was approached by two suspects who kicked him repeatedly in the head and subsequently ran off.
“The victim was taken to a Central London Hospital where he was treated for concussion and a cut to his left eyelid. He remains in hospital in a stable condition.”
Police are keeping an open mind as to the motive for the attack.
Mr Sallon, who has been a fixture on the London club scene for decades, is a good friend of Boy George and Jodie Harsh and was one of the original Blitz Kids.
Both tweeted of their shock at the attack. George said he had visited Mr Sallon in hospital and that he should make a “complete recovery”.