Published Thursday, 22 May 2014
Police released a photograph of the man whose body was found. (© PSNI)
The 54-year-old, originally from Belfast, had not been seen since 23 April.
His remains were discovered at Magilligan Point on Tuesday by a group of primary school children who were on a field trip. Police said the death is not being treated as suspicious.
A spokesperson for the PSNI on Thursday said: "A post mortem has been carried out following the death of a man whose body was discovered at Magilligan Point on Tuesday 20 May. Police have confirmed that the body is that of missing person John McIlwaine."
Officers are now trying to piece together Mr McIlwaine's movements before his death.
He was last seen in the Strand Road area of Portstewart last month and anyone who saw him or may have spoken to him has been asked to get in touch with officers.
Police said: "At this stage, police are not treating the death as suspicious, but they are keen to speak to anyone who may have saw or spoke with John McIlwaine in the days or weeks after Wednesday 23 April.
"If you can assist detectives, please contact them on the new non-emergency number 101."
© UTV News