The PSNI are investigating the sudden death of 25-year-old Conall Kerrigan.
Mr Kerrigan was found near Bank Place in Derry at around 10:20 pm on Sunday night.
It is believed that Conall had been in the Metro Bar on Saturday night and left at around 2 am on Sunday morning.
Mr Kerrigans family reported him missing on Sunday afternoon.
Police are appealing for witnesses.
His death is currently being treated as unexplained.