George, who got engaged to Kerry last year and welcomed a baby daughter with her in April, was apparently found darting around outside the couple's home at 6pm while shouting that someone was trying to kill him.
A neighbour has since told newspaper reporters that the former rugby player and Gladiator was seen "running in and out of cars" while appearing to be "agitated", so a female motorist called 999.
A police spokesman confirmed that a 34-year-old man was detained, saying: "Thames Valley Police can confirm that officers were called to a road in Chinnor shortly after 6pm following concerns for the welfare of a man.
"A 34-year-old man was detained at the scene and taken to the John Radcliffe Hospital in Oxford, where he was detained under the Mental Health Act. He was later discharged."
It has since been reported that the man was George.
According to the Daily Star, a rep for Kerry had no comment last night.
Reveal has also contacted Kerry and George's rep for a comment.
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