Detectives investigating a claim of a "sexual nature" involving a boy aged under 16 have searched a house in Sunningdale, Berkshire that belongs to Sir Cliff Richard. Sir Cliff, who is out of the country, said the allegation, which dates from the 1980s, is "completely false".
The alleged abuse is claimed to have taken place on a child in the South Yorkshire area.
South Yorkshire police said: "South Yorkshire police has gained entry to a property in the Sunningdale area of Berkshire. Officers are currently searching the property. A search warrant was granted after police received an allegation of a sexual nature dating back to the 1980s involving a boy who was under the age of 16 at the time. No one has been arrested and the owner of the property was not present."
The investigation is not connected to Operation Yewtree, set up by the Metropolitan Police to investigate allegations in the wake of the Jimmy Savile sex abuse scandal.
Sir Cliff said in a statement: "For many months I have been aware of allegations against me of historic impropriety which have been circulating online.
"The allegations are completely false. Up until now I have chosen not to dignify the false allegations with a response, as it would just give them more oxygen.
"However, the police attended my apartment in Berkshire today without notice, except it would appear to the press.
"I am not presently in the UK but it goes without saying that I will cooperate fully should the police wish to speak to me. Beyond stating that today's allegation is completely false it would not be appropriate to say anything further until the police investigation has concluded."
According to the BBC's Tom Burridge in the Algarve, Portugal, the singer left his home there on Thursday morning and has travelled with his sister to another part of Portugal for a few days.
Sir Cliff, born Harry Webb, has sold 21.5 million singles and has had at least one UK top five album in each of the last seven decades. He was knighted in 1995 and performed at the Queen's Diamond Jubilee concert at Buckingham Palace in 2012.