Sir Cliff Richard has today vehemently the claim that he committed a sexual offence with a boy under the age of 16 in the 1980s.
The 73-year-old's luxury apartment in Sunningdale, Berkshire, was searched today for five and a half hours hours by eight plain-clothes police officers.
A police spokesman said the allegation involved a boy under 16 years of age and dated from the 1980s in the South Yorkshire area.
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Celebrity appearance: Sir Cliff is believed to be in the Algarve region of Portugal, where he gave an interview to Kiss FM on Sunday (pictured) less than a week after raising thousands in a charity gig at his vineyard
'Completely false': Sir Cliff, pictured at the FM Algarve studio on Sunday, has vehemently denied a claim that he committed a sexual offence with a biy under the age of 16 in the 1980s.
Sir Cliff released a statement calling the allegation 'completely false' and says he will 'co-operate fully' with the police investigation.
It is understood the alleged abuse is claimed to have taken place at a major rally at Sheffield's Bramall Lane stadium in 1985, which was hosted by the US evangelist preacher Billy Graham.
Sir Cliff was known as a dedicated follower of the preacher, who called his huge events 'crusades', and appeared on stage at his campaign meetings as early as 1966.
A spokesman for South Yorkshire Police said today three of its officers searched the property in Berkshire assisted by five officers from Thames Valley Police.
Home from home: Sir Cliff's property in the Algarve, where he is thought to be staying.
'Police have gained entry to a property in the Sunningdale area of Berkshire,' the spokesman said.
'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 search ended at around 3.30pm, five unmarked cars, each with three to four people inside, were seen leaving the gated development.
Police are believed to have been at the property for around five hours.
The search is not connected to Operation Yewtree, police said, but officers have been notified, a South Yorkshire Police spokesman added.
Sir Cliff today 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.'
The BBC reported that the 73-year-old entertainer is currently in his home in the Algarve in Portugal.
A Thames Valley Police spokesman said: 'We can confirm that Thames Valley Police has today assisted South Yorkshire Police with the execution of a search warrant at an address in Sunningdale, Berkshire.'
Investigation: Stills from news footage showed police arriving at the home of Sir Cliff Richard near Sunningdale, Berkshire. A convoy of cars was seen entering the complex before leaving at around 3.30pm
Sir Cliff Richard bought his apartment in the prestigious Charters complex in Sunningdale, Berkshire, for £3.1million in 2008. Police were said to be searching the property in relation to an alleged historical sex offence
Search: People, thought to be police officers involved in the search, inside the property
Search team: Police officers in unmarked cars leave Sir Cliff's Ascot home after searching the apartment
In convoy: The convoy of cars leaves the exclusive Charters estate.
Sir Cliff's publicist Lisa Davies said she was not previously aware of the allegations.
Born Harry Webb in 1940 in Lucknow, India, Sir Cliff's father was a catering contractor for Indian Railways while his mother worked as a matron at a girls' school.
After moving back to Britain where he lived in Carshalton, south west London, he shot to fame as a young heartthrob with the style of chart-toppers like Elvis Presley and his musical hero Little Richard.
The singer had a string of hits in the 1950s and 1960s with his backing group The Shadows and is the only singer ever to have had Number One singles in five consecutive decades.
The gates to Sir Cliff Richard's luxury £3.1m property, which he bought in 2008, remained closed this afternoon, with no obvious sign of police activity.
Earlier a police helicopter had circled above the Charters development but had left a short while later, with no one entering or leaving the site.
The development near Ascot, Berkshire, sits behind 10ft white walls and brown metal gates, with a security camera overlooking the wall.
The luxury apartments are located in more than 20 acres of private grounds described as 'an iconic development of two and three bedroom apartments offering the very best in contemporary living'.
The facilities include a health spa, pool and tennis complex with a 24/7 concierge service and security.
Films such as Summer Holiday - in which he famously took a red London bus around Europe - made him one of the most recognisable faces in the country.
He finally changed his named to Cliff Richard formally by deed poll in 1980, the same year he was made an OBE for services to music and charity.
Preacher: The allegation is understood to relate to a major stadium rally in Sheffield by US preacher Billy Graham in June 1985. Pictured: Cliff Richard with Billy Graham at a 1984 rally at Birmingham's Villa Park
Evangelist: Billy Graham speaking at the 1985 event in Sheffield to which the allegation is understood to refer.
He was knighted in 1995, also for services to music and charity, and sang at the Queen's Diamond Jubilee Concert at Buckingham Palace in 2012.
In 2010 it was reported that Sir Cliff had moved to Barbados permanently after selling his house in Weybridge, Surrey, in 2006.
He was quoted as saying: 'I'm officially a non-resident, although I will always be British and proud of it.'
A devout Christian, Sir Cliff revealed in 2008 how had shared his home for many years with a former Roman Catholic priest who he described as a 'companion' and a 'blessing'.
Sir Cliff met Father John McElynn during a trip to New York in 2001 and said that McElynn took a break from the priesthood soon after.
Tennis fan: Sir Cliff is a regular attendee at Wimbledon and visited last month with the TV personality Cilla Black
Fan: Sir Cliff, pictured at Wimbledon, has many celebrity friends including the sports commentator Sue Barker
In his autobiography My Life, My Way, he wrote: 'He hadn't any thought at the beginning of giving up the priesthood, but when it became clear he was thinking of the possibility, I suggested he might help me with some charitable projects.
'That was seven years ago and our arrangement has worked out really well. John now spends most of his time looking after my properties.
'He has become a companion, which is great because I don't like living alone, even now.'
The book was also an opportunity to hit back over speculation over his personal life, including rumours that he may have been gay.
'I am sick to death of the media's speculation about it,' he wrote.
'What business is it of anyone else's what any of us are as individuals? I don't think my fans would care either way.'
He gave an interview to Kiss FM Algarve on Sunday, describing himself as 'fit and well and doing my best'
THE LOVES OF SIR CLIFF RICHARD
'Passionate': Sir Cliff with Una Stubbs.
According to his biographer, Steve Turner, Sir Cliff has only had three significant partners.
It has been widely reported that he lost his virginity at 18 to Carol Harris, the wife of Shadows bandmate Jet.
In a biography he dismissed the affair as mere infatuation, claiming that what happened between them was 'not right', and painting her as his seductress.
At 22, he had a passionate affair with actress Una Stubbs, then 24, on the set of the film Wonderful Life, released in 1964.
In the early Eighties he enjoyed a three-year friendship with former Wimbledon ace Sue Barker, even at one point considering marriage.
In 2010 a letter written by Sir Cliff to then girlfriend Delia wicks in 1961 emerged.
In the Dear John letter, sent as he toured Australia, he wrote: ‘Being a pop singer I have to give up one priceless thing – the right to any lasting relationship with any special girl.
‘I’ve just had to make, probably, one of the biggest decisions I’m ever going to make and I’m hoping that it won’t hurt you too much.’
In the 1980s, he considered marriage to Sue Barker, the former tennis champion and host of the BBC’s Question of Sport.
Sir Cliff is often accompanied by his trusted companion and friend, former Roman Catholic priest John McElynn.
Once an American missionary, Mr McElynn has been friends with the singer for more than a decade and looks after his property portfolio.
Sir Cliff once said of him: 'He has become a companion, which is great, because I don't like living alone'.
He gave an interview to Kiss FM Algarve on Sunday, describing himself as 'fit and well and doing my best'.
He was excited about new material, telling presenter Owen Gee: 'I'm going back to Nashville to make Volume 2 of the Fabulous Rock n Roll Songbook so that'll be at the end of October.'
In the radio interview he also talked about his charity work, and a good friend who had spent much of her life looking after children who had been through hardship.
He said: 'I always felt that when it comes to children their suffering seems so unfair because they're so young and they've done nothing in their lives, they haven't done anything evil to deserve it. They don't deserve it.'
He told the interviewer he was planning to record a song this October with the voice of Elvis Presley from beyond the grave.
Of the publicity push for his latest album, he said: 'There's no guarantee that the mainstream radio stations anywhere in the world now will play records by people of a certain age.
'I did 125 different TV and radio interviews, performances as well, and it was the toughest time I ever had. I had to tell my office I can't do this again, I'm not 18, and I was jet-lagged.'
Sir Cliff Richard and his close friend, the former priest Father John McElynn, in Barbados last year
Fame: The singer shot to fame in the 1950s and 1960s with his backing group The Shadows and is the only singer ever to have had Number One singles in five consecutive decades, ending with Mistletoe and Wine.
Last week Sir Cliff hosted a fundraising gig at his Quinta do Miradouro vineyard in the Algarve which raised more than €10,000.
The funds went to the Peta Birch Community Association, which was set up in memory of an Algarve resident killed in a road crash last year.
Sir Cliff's vineyard, Adega do Cantor, is in the centre of the Algarve region near the tiny village of Guia and on top of a hill named Quinta do Miradouro.
After 40 years of visiting the Portuguese region Sir Cliff had the idea of starting the vineyard, which is run by his friends Nigel and Lesley Birch.
Its website says: 'Our aim is to produce the highest quality wine that the region can offer using a combination of traditional and innovative modern winemaking techniques.
'Sir Cliff is very much involved in producing the wine. When in Portugal he is often seen getting his hands dirty in the vineyard or indeed his feet dirty in the winery.'
Police said the allegations dated from the 1980s. Pictured, Sir Cliff on the day he received his OBE in 1980 (left) and, right, the entertainer in 1989
THE PETER PAN OF POP: SIR CLIFF'S SEVEN DECADES OF HITS
At 56 years into his showbusiness career Sir Cliff has sold more than 250 million records and still plays live to audiences around the world.
His first single Move It was released in August 1958 and a string of others followed, with the artist building a reputation for his energetic live performances and catchy hits.
He scored his first number one less than a year later in July 1959 with Living Doll, which remained at the top of the charts for six weeks.
Thirteen more number ones followed including eight more in the 1960s, among which were the hits Summer Holiday and Congratulations.
From then he scored a number one hit in every decade until the 1990s - including We Don't Talk Anymore in 1979, Living Doll in 1986, Mistletoe and Wine in 1988 and Saviour's Day in 1990.
Even as Beatlemania took hold, Sir Cliff was a familiar feature of the charts, although the gaps between his number ones increased.
His conversion to Christianity took place in 1964 and he considered quitting the music business, particularly as a man who at one stage had been deemed 'too sexy for TV'.
But friends advised against it and his popularity was undimmed, setting him a world away from the wild behaviour of some rock stars.
In 1968 he became the UK's Eurovision Song Contest entrant, singing Congratulations and missing out on a win by a single point.
He returned to the competition again five years later with Power to All Our Friends, which finished third.
Sir Cliff later devoted a number of years to getting his stage musical Heathcliff off the ground, in which he starred and which provided a chart hit with Misunderstood Man.
His devoted fanbase swung into action in 1999 when Radio 2 failed to playlist his single Millennium Prayer, and the publicity surrounding the single gave him his biggest hit for nine years.
His releases became less prolific as the 21st century dawned but Sir Cliff continued to be a popular live performer with fans often camping out to snap up tickets for his shows.
But the 'Peter Pan of pop' could claim to be a favourite of royalty, numbering among only a few celebrities who were invited to a tenth anniversary memorial service in August 2007 to mark the death of Diana, Princess of Wales.
He also led a celebrated singalong at a rain-sodden Wimbledon Centre Court the following year in a performance which included Summer Holiday and Bachelor Boy.
His last album The Fabulous Rock ‘n’ Roll Songbook, released in November last year, was advertised as his 100th and featured covers of songs by Buddy Holly, Elvis Presley and Chuck Berry.