An appeal had been launched to find a man who discharged himself from hospital and is need of urgent treatment.
The 43-year-old was wearing boxer shorts and a hospital gown at the time of his disappearance at 12.10pm on Friday (September 29).
Zdeno Puskas requires serious medical attention and may act irrationally due to a head injury, police said.
Officers in Westminster are concerned for his wellbeing and urge anyone with information on his whereabouts to get in touch.
He has been described as white, 5ft 6ins, of medium build, bald and with a black goatee beard.
Anyone with information can call police on 101 or Missing People on 116000.
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