A seriously ill former Royal Ballet School student is missing after leaving hospital without shoes in freezing conditions.
Ashleigh Fair, 19, left the Royal Berkshire Hospital at around 9.30am on Thursday, Thames Valley Police said.
She is believed to have taken a taxi from Southern Hill, Reading, and arrived at Marble Arch in central London at 11.37am.
Ms Fair has a life-threatening condition and requires urgent medical assistance, Scotland Yard said.
She was dressed in a green and pink knitted jumper, black tracksuit bottoms and pink socks when she left the hospital, but was not wearing shoes.
Police are appealing for anyone with information about her whereabouts to come forward.
Detective Sergeant Emily Evans, investigating officer at Thames Valley Police, said: “We are very concerned for Ashleigh’s wellbeing.
“She is vulnerable and unwell, and we are also concerned that she is not wearing appropriate clothing for the weather.
“I would ask anyone who sees her, or has any information which they think could lead to us locating her, to please call us on 999.”