Police and Shomrim community security volunteers have appealed for help after a strictly Orthodox man went missing.
Simcha Rosenbaum was last seen on Thursday at Homerton Hospital, in Hackney, east London.
The 21-year-old had not been seen more than 24 hours later on Friday afternoon.
In their appeal police said anyone who sees Mr Rosenbaum should contact officers on the 101 telephone number and quote reference number 15MIS033998.