The Duke of Edinburgh travelled from Norfolk on Friday morning to the King Edward VII Hospital in London for observation and treatment in relation to a pre-existing condition. In a statement Buckingham Palace said: "The admission is a precautionary measure, on the advice of His Royal Highness' Doctor." Prince Philip, 98, is expected to be in hospital for a few days - he was not taken by ambulance and it was a planned admission.
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Following Philip's admittance, there were police officers guarding the main entrance to King Edward VII's Hospital in Marylebone, with further officers stationed along the street.
The Duke retired from public duties, aged 96, in August 2017 after carrying out more than 22,219 engagements since 1952. It is believed that he divides his time between Wood Farm in Sandringham and Windsor Castle. The Duke was last seen in public for Lady Gabriella Windsor and Thomas Kingston's wedding at St George's Chapel in Windsor in May 2018.
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The Queen and Prince Philip
He attended the weddings of his grandson Prince Harry to Meghan Markle, and granddaughter Princess Eugenie to Jack Brooksbank in 2018. In November, the Queen and the Duke marked their 72nd wedding anniversary, however the monarch was back in London to present Sir David Attenborough with an award on that evening.
It comes after the Queen arrived at King's Lynn rail station on Friday afternoon by commuter train to begin her Christmas break in Sandringham. The 93-year-old monarch carried out her second State Opening of Parliament in the space of two months on Thursday after the UK general election on 12 December.
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The Queen arrived in Sandringham on Friday afternoon
In January, the Duke made headlines after he was involved in a car crash on the Sandringham Estate. His Land Rover Freelander collided with another vehicle, leaving the two women in the Kia with minor injuries. Philip's car overturned but he managed to escape unscathed.
The Duke apologised to the occupants of the Kia and in a handwritten letter told passenger Emma Fairweather, who broke her wrist in the accident, that he was "very sorry". He subsequently gave up his license and did not face prosecution over the road accident.
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