The disappearance of Belgian backpacker Theo Hayez from Byron Bay has been referred to the New South Wales coroner, bringing the official police search to an end.

Key points: Theo Hayez went missing on May 31 after a night out in Byron Bay

Theo Hayez went missing on May 31 after a night out in Byron Bay He was due to return home to Belgium just a week after his disappearance

He was due to return home to Belgium just a week after his disappearance Anyone with information is still being urged to contact police

The 18-year-old was last seen leaving the Cheeky Monkey's nightclub on Jonson Street at about 11:00pm on Friday, May 31.

Pings from his mobile phone were detected near the Cape Byron lighthouse the next day, but investigators believe it was on sleep mode when it sent its last signal.

A cap similar to the one he was wearing on the night he vanished was recently found in bushland near Tallow Beach.

The ABC understands forensic tests failed to produce a DNA match, but that those close to the family believe it belonged to Mr Hayez.

On Monday a police spokesperson confirmed the police search had come to an end.

"Detectives from Tweed and Byron Police District have referred the matter to the NSW Coroner," she said.

"The family wish to thank the public and the community volunteers for their ongoing support. They have requested their privacy at this time."

Hundreds of volunteers joined family members for a sunset candlelit vigil at Clarkes Beach on Sunday in memory of Mr Hayez.

"Lighting the Night tonight was a beautiful and emotional honouring of Theo, to express our ongoing hope and to encourage people to keep coming forward with information," a post read on the Looking for Theo Hayez Facebook page.

"Thank you to everyone who came along to support Theo's family."

A vigil was held for Theo Hayez at Byron Bay on Sunday night. ( Facebook: Looking for Theo Hayez )

Mr Hayez's godfather Jean-Philippe Pector was emotional as he spoke of the sadness inflicted on the family.

"We've got a strong belief and also because we know how Theo is and what he would do, he would not spend a night alone outside in an environment he didn't know, so we strongly believe that he was with people on that night," he said.

He also thanked the hundreds of volunteers, some of whom put their life on hold for three months to participate in the search.

Mr Hayez's father Laurent Hayez returned to Byron Bay two weeks ago, but the ABC has been told he has been struggling "more so than ever".

The Belgian backpacker had been travelling for eight months and was planning to return home when he vanished without a trace in May.

He was staying at the Wake Up! Hostel in Byron Bay, and it took staff almost a week to report his disappearance to police.

Management have repeatedly declined ABC requests for an interview, saying it would be inappropriate to comment while an active investigation takes place.

A huge air and land search operation was conducted around the Byron Bay area, but it failed to locate any trace of Mr Hayez.

Anyone with information is still being urged to contact police.

