Tasmania Police to formally join renewed search for missing Belgian tourist Celine Cremer

Police will join the renewed search for a Belgian tourist who went missing in Tasmanian wilderness, following the discovery of her mobile phone on Saturday.

Celine Cremer disappeared after embarking on a bushwalk at Philosopher Falls near Waratah in north-west Tasmania in June 2023.

Her car was found near the walking track, but searches at the time found no other trace of the 31-year-old.

Ms Cremer's friends and family began a private search on Saturday, and a volunteer found the missing tourist's phone within hours.

The search was postponed on Sunday because of bad weather, but Tasmania Police inspector Andrew Hanson said police search and rescue personnel and trained volunteers would be added when it resumed.

"It's fair to say hopes are up," Inspector Hanson said.

"But I have to caveat that expectation with the stark reality this is not easy work.

Volunteer and local Tony Hage found the mauve-coloured Samsung phone on Saturday.

Mr Hage has been involved in previous police searches and has conducted his own private searches for Ms Cremer.

Inspector Hanson described the find as "opportunistic" and headed off criticism police hadn't discovered it themselves in 2023.

"It's a fair question," he said.

"The weather during that time was considered poor. The average temperature was minus 2 degrees and there was significant rainfall and snow down to ground level.

"I'm certainly not going to stand here and say we couldn't do things differently, because as an organisation we value accountability and we'll reflect on everything."

Inspector Hanson said the sun had been shining on the phone at the right time, leading to the breakthrough discovery.

He described the phone as damp but in good condition, and said it was being forensically examined.

Police believe Ms Cremer left walking track, became lost

The working theory for police, he said, was that Ms Cremer had likely gone off track to take a straight line to the Philosopher Falls car park when it was getting dark.

"I know that sunset on that day was at 4:57pm and in winter in those weather conditions, and particularly in that canopy, it would have almost seemed like night-time had fallen at that 4 o'clock mark," he said.

"Our theory is that Celine has either accidentally veered from that track or has made a decision to follow a more direct route from her position back to the Philosopher Falls car park.

He said a tracking app on her phone indicated the shortcut.

"She's reached a high point on a hill where the phone has spoken to the satellites and we're able to retrieve some data.

"That data stops at that point so our theory is Celine then continued on that pathway down the hill where the coverage wasn't as good … and it's our belief she's either lost or dropped her mobile phone, couldn't find it in the dark and has made a decision to continue on that straight line towards her car and unfortunately become lost."

Inspector Hanson said police would join but not lead the search, and that they would likely help search the line from where the phone was found back to the car park.

"The environment hasn't changed and, even though it is summer and we are putting some effort into that search, there's no guarantee we might find anything else," he said.

The last confirmed sighting of Ms Cremer was in Waratah on June 17,  2023, the day she is believed to have set off on the walk.

She was reported missing on June 26.