Anthony Knowles Aged 48 has absconded a secure mental health unit after he was granted permission to be released for a trip, he was been escorted by prison staff when he disappeared.
He was authorised leave from the John Howard Centre in Hackney, East London.
Knowles was wearing a grey tracksuit and black cap when he was last seen. He is described as walking with a limp, is 5ft 8in, heavily built, has tattoos on both arms and a scar across his left eye.
Members of the public are warned not to approach Knowles and to dial the police emergency number on 999 if seen.