The 19-year-old Canadian national was found on a beach at a popular Queensland tourist spot early on Monday with markings that indicated she had been "interfered with" by dingoes.
But police would not speculate on the cause of death, saying the woman's body had been discovered about 90 minutes after she went for an early morning swim on K'gari, formerly Fraser Island.
Police were called to the beach near popular tourist spot the SS Maheno shipwreck about 6.35am, after reports a woman had been found unresponsive.
Two men were driving up the beach when they saw about 10 dingoes "near an object" on the beach, Inspector Paul Algie said.
Upon closer inspection they made a grisly discovery.
"It was obviously a very traumatic and horrific scene for them to uncover," Insp Algie said.
"I can confirm there was markings on her body consistent with having been touched and interfered with by the dingoes."
Police said it was too early to speculate on the woman's cause of death.
She had arrived at the beach about 5am for a morning swim.
Detectives are trying to piece together what happened in the 90 minutes leading up to the discovery of her body.
A post mortem is set to be completed on Wednesday.
"We simply can't confirm whether this young lady drowned or died as a result of being attacked by dingoes," Insp Algie said.
"We do acknowledge that there is a large amount of community interest in this story and we will endeavour to provide further details when the post mortem is conducted."
The woman had been working with a friend from Canada at a backpackers on the island for about six weeks.
"She's obviously extremely traumatised ... and has helped police make contact with (the victim's) family over in Canada via the Royal Canadian Mounted Police," Insp Algie said.
The local community has been left reeling from the tragedy.
"Police on K'gari are locals ... they are absolutely horrified and shocked at what's occurred - this is an incident that impacts everybody heavily,'' Insp Algie said.
He warned against going near dingoes.
"K'gari is a wilderness area. Dingoes are wild animals ... and need to be treated as such," he said.
"I implore all people that visit K'gari, which is a beautiful place, that you do not go near dingoes."
About 200 dingoes roam free on K'gari and are a protected native species at the national park.