In a development that appeared to draw a line under one part of a sprawling drama that gripped the nation – even as other elements of it continued – a senior FBI agent said human remains matching a description of the young woman had been found at a camp site, located about 20 miles north of Jackson.
FBI senior advisory agent Charles Jones said on Sunday afternoon that while there had not at this point been a 100 per cent identification of the remains, the authorities had informed the parents of Ms Petito, to whom he issued his condolences.
“The cause of death has not been determined at this time,” said Mr Jones, at times his voice faltering.
“We appreciate your continued support and patience as we work through this process.”
Ms Petito, 22, has been missing since last month. She had been on a cross-country trip from her native Long Island with her boyfriend, Brian Laundrie, 23 – who drove her van back to Florida without her.
The authorities had focused their search on the Spread Creek Road dispersed camp in Grand Teton National Park. Rangers from the National Park Service blocked the public and the media from entering the site, while campers who had been using it were told to be gone by the time the search started on Saturday.
It was believed that the campsite was one of several that Ms Petito had listed as being among those they planned to visit.
Late on Saturday, a couple, on a road trip across America, posted video they say shows the white Ford Transit van used by Ms Petito and her boyfriend parked at the campsite that was being searched by the FBI.
The video was posted by Jenn and Kyle Bethune, who transformed a 1983 sliver eagle bus to hit the road, and post video updates at their page Red White & Bethune, which is subtitled “Showing America through our Lens”.
“This is at the Spread Creek dispersed camping area. We got there and there was a huge gravel lot and we decided we wanted to try to drive more toward the back because we’d heard the views were better back here. So we were heading back on this long dirt, gravel road,” Mr Bethune said, narrating the video he posted on Saturday night.
His wife continued: “And we came across a white van that had Florida plates, a small white van. We were going to stop and say hi because we’re from Florida too, but the van was completely dark there was nobody there so we decided to continue on our way.”
At the press conference on Sunday, Mr Jones thanked the public for its help.
“We appreciate the tremendous support from the public. The support from the public's response to request of tips has been remarkable,” he said. “We continue to seek information from anyone who utilise the spread Creek dispersed camping area between the dates of August 27 and August 30.”
After, asked by The Independent how important that information had been, he said: “It was vital”.
Mr Laundrie himself was reported missing on Friday by his parents. He had been declared a person of interest in Ms Petito’s disappearance but had refused to speak to investigators prior to his disappearance.
The couple had been involved in an altercation last month in Moab, Utah and police responded but no charges were filed. He and Ms Petito had been documenting their coast-to-coast journey on social media.
“I can confirm that the coroners officer was dispatched by a deputy coroner on the scene to recover a body that was found in the forest,” Teton County Coroner Dr Brent Blue said on Sunday. It is understood the autopsy may not be carried out until Tuesday.
As authorities held a press conference announcing the possible tragic find in Wyoming, officials in Florida continued combing the area where Mr Laundrie was believed to be. His family said they last saw him on Tuesday but did not report any concern to police for several days.