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(CNN) --
Buckingham Palace reported Thursday that Queen Elizabeth's doctors are concerned about her health and have recommended medical supervision.
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"Following further assessment this morning, the Queen's doctors are concerned for Her Majesty's health and have recommended that she remain under medical supervision," a statement read.
Buckingham Palace added that "the queen remains comfortable and at Balmoral Castle" in Scotland.
A royal source told CNN on Thursday that members of the queen's immediate family have already been told about concerns about her health.
And he dismissed rumors that the monarch has suffered a fall.
News in development...
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