Three bones found at Flynns Beach in Port Macquarie have been confirmed as those of Erwan Ferrieux

The 21-year-old went missing at Port Macquarie's Shelly Beach along with Englishman, Hugo Palmer on Sunday, February 17.

Spear fishers uncovered the first human bone at Flynns Beach on June 15 and later another two were found at Flat Rock, east of Nobby Head on June 17.

Mid North Coast Local Area Commander Superintendent Paul Fehon said the three bones were believed to be those of Mr Ferrieux.

"DNA comparison of the three bones found in early June have found that they did come from the same male person," Supt Fehon said.

"That DNA analysis has also confirmed that it came from a DNA comparison from the vehicle that was utilised by two missing backpackers at the time.

"We believe from the DNA comparisons that it belongs to Erwan Ferrieux."

Forensic samples from missing travellers' rented silver Commodore station wagon were matched to the bones.

A fourth bone was located by passers-by at Port Macquarie's Rocky Beach, north of Flynns Beach on Sunday (July 14) afternoon.

The small bone is believed to be human and will undergo forensic examination in Newcastle to be compared with missing person records.

"Yesterday afternoon a member of the public retrieved a bone about 300 metres north of Flynns Beach which we believe is possibly human," Supt Fehon said.

"We wouldn't be speculating at all (if the fourth bone is linked to the others) and we will be awaiting further tests to confirm that.

"This bone was located in a different area, north of the beach whereas the other three bones were located in a southerly area.

"It will be a number of weeks before we are able to confirm the testing of the new bone.

"Our thoughts are with the families of all those missing people each time a discovery like this occurs."

Police are continuing their investigations without the use of Sydney police divers this week.

A search operation will be conducted today (July 15) with the NSW State Emergency Service.

"We'll be conducting a search with the NSW SES due to the location it was found, it was near the shoreline," Supt Fehon said.

"It has been beneficial in people (members of the public) locating these bones, always just try to preserve the bones, record the location and advise police as soon as possible."

A community service was held at Shelly Beach for missing men, Hugo Palmer and Erwan Ferrieux on February 24.

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