An appeal has been launched to find an elderly man deemed high risk due to the advance stages of his dementia.
Abdoulahi Ndoye from Hackney went missing on Wednesday and was last seen in Lea Bridge Road at the junction with Albany Road in Leyton.
The 74 year-old dementia sufferer is known to frequent Waltham Forest and has strong links to Beckton in Newham where he recently lived until moving to Hackney.
It is understood Mr Ndoye is not in possession of any money or his Freedom Pass.
He is described as black, 6 ft tall, of slim build with black unkempt hair and was last seen wearing a black jacket with a big collar, black jeans and black boots.
Detective sergeant Paul Ridley of Hackney CID said: "I am very concerned regarding Abdoulahi's welfare due to his deteriorating health.
"He has only been living in Hackney for approximately a week and may have attempted to return to Newham which he knows well.
"He frequents the public transport network, particularly buses and I would request that the public's focus is directed towards these areas.
"He has left home without any money and no means of contact."
Anyone who has seen Mr Ndoye is asked to contact Hackney police on 020 8721 7777.