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The husband of Queen Elizabeth II, Prince Philip, has been hospitalized just as Britain holds major celebrations marking the queen's 60th anniversary on the throne.

Palace officials said the 91-year-old prince -- whose official title is the Duke of Edinburgh -- was sent to the hospital Monday "as a precautionary measure" after developing a bladder infection. He is expected to remain in the hospital under observation for a few days.

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Prince Philip joined the queen and senior royals Sunday on the River Thames for a pageant as part of Queen Elizabeth's Diamond Jubilee celebrations.

He will miss a star-studded concert Monday evening at Buckingham Palace as well as a luncheon and carriage procession on Tuesday. A palace statement said Prince Philip regrets not being able to participate. "He is, understandably, disappointed about missing this evening’s Diamond Jubilee Concert and tomorrow’s engagements."

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