King Charles has attended church in Sandringham in his first public outing since Buckingham Palace announced his cancer diagnosis.
The King waved to members of the public as he walked outside St Mary Magdalene Church with his wife, Queen Camilla.
It comes after the King, 75, thanked people on Saturday for their "support and good wishes" since the news.
He said all those affected by cancer knew "such kind thoughts" were "the greatest comfort and encouragement".
Around 100 well-wishers were gathered on Sunday as the King walked into church in Sandringham, briefly speaking with the Rev Canon Dr Paul Williams.
Crowds gathered around the gates of the private estate, but were not allowed to enter the grounds - which are closed to the public until Easter.
King Charles left Clarence House, London, for his Norfolk residence on Tuesday, accompanied by the Queen. His youngest son, the Duke of Sussex, had flown in from the US for a brief visit earlier that day.
The King's cancer was detected while he was undergoing treatment in London for an enlarged prostate in January.
While the type of cancer has not been disclosed, the Palace confirmed it was not prostate cancer.
King Charles has stepped back from all public-facing duties while he receives treatment, with senior royals - including Queen Camilla and the Prince of Wales - taking on his duties for some events.
In his message of thanks, the King wrote: "It is equally heartening to hear how sharing my own diagnosis has helped promote public understanding and shine a light on the work of all those organisations which support cancer patients and their families across the UK and wider world.
"My lifelong admiration for their tireless care and dedication is all the greater as a result of my own personal experience."
King Charles's cancer diagnosis
Before his message on Saturday, the Queen spoke at an event at Salisbury Cathedral on Thursday and described the support as "very cheering".
Prince William also expressed gratitude for messages of support for his father and for his wife, the Princess of Wales, as she recovers from abdominal surgery.
She is not expected to return to royal duties until after Easter.
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