The 17-year-old was meant to fly from Bundaberg Airport to visit her boyfriend in Western Australia on May 15 but, according to police, she never checked in for her flight or entered the terminal.
Queensland Detective Inspector Craig Mansfield said further forensic testing would be carried out to formally identify the remains.
“As a result, a crime scene is still established there at the moment,” Mansfield said.
“We have been in contact with Pheobe’s family to advise them of this development.
“Understandably, this caused great distress to them, however they’re supportive of the information that they’ve been receiving along the way.”
Mansfield said the remains were found in bushland and police believe they were not buried.
Additional testing will be carried out during the day to formally identify the remains.
“Our forensic capabilities will hopefully be finished there today,” Mansfield said.
“The area is in an unforgiving terrain, so it may take some time to finish that examination.”
Mansfield said the 17-year-old’s travel luggage and phone has not been found.
Pheobe’s housemates, 34-year-old James Wood and his partner, 33-year-old Tanika Bromley, were charged with one count of murder and two counts each of interfering with a corpse after they were arrested in Bundaberg on Thursday night.
“We are engaging with legal representatives for both of those accused,” Mansfield said.
“This particular area that has been searched at the moment is actually an extension of our original search area.”
Police continue to appeal for any information about Pheobe or the movement of her housemate’s grey Hyundai IX35 with registration 414EW3 between May 15 to 18 in the greater Gin Gin area.
Investigations are ongoing as Wood and Bromley remain before the courts.
Pheobe’s mum Kylie Johnson said she did not think her heart could break any more after receiving the news last night.
“I didn’t think my heart could break any more than it did when you went missing, or when the charges were laid, but this, this is ripping me apart,” she said.
