A woman who was dubbed the "Angel of Woolwich" for confronting the killers of soldier Lee Rigby has been detained under the Mental Health Act.
Ingrid Loyau-Kennett, 49, was praised by Prime Minister David Cameron for her actions shortly after Fusilier Rigby, 25, was killed near his barracks in Woolwich, London, in May last year.
But it is understood she was detained on Monday after police were called to an address in Helston, Cornwall over concerns for the welfare of a woman.
A Devon and Police spokesman said: "On Monday June 30 following a report for a concern for welfare a 49-year-old woman from Helston was detained under the Mental Health Act.
"She was detained at about 4.20pm and conveyed to the Royal Cornwall Hospital and released into the care of the NHS."
Ms Loyau-Kennett was under investigation following claims a Tesco worker was racially abused at a store in the town last Friday.
A Tesco spokesman said: "We are aware of an incident which took place at our Helston store on Friday. Colleagues at the store are helping the police with their inquiries."
Ms Loyau-Kennett received national acclaim for calmly talking to armed Michael Adebolajo and Michael Adebowale after they murdered Fusilier Rigby in the street.
On the first anniversary of the killing, Ms Loyau-Kennett spoke at the scene where she checked Fusilier Rigby's pulse and confronted Adebowale.
She said: "It has been a waste of three lives and, of course, a year on I still think about Lee Rigby's mother losing a son. It's a tragedy. I don't have flashbacks but I have been very emotional lately.
"This street looks like a normal street now but I can still see the body, see the crashed car and see the bloodied hands."
Adebolajo, 29, was given a whole life sentence, and Adebowale, 22, told he must serve a minimum of 45 years' imprisonment at the Old Bailey in February.