Autopsy scheduled for body thought to be Gabby Petito; fiance still missing

Medical examiners in North Port, Florida, were scheduled to conduct an autopsy on Tuesday on a body found in Wyoming, seeking to determine if it is Gabby Petito, the 22-year-old "van life" traveller whose disappearance has gripped Americans.

The examination of the remains, which were discovered Sunday in a remote area of Bridger-Teton National Forest, in western Wyoming, takes place as police and FBI agents search for her fiance, Brian Laundrie.

Investigators have called Laundrie, 23, a "person of interest" in the sensational case. His parents told FBI agents they last saw him one week ago, when he told them he was planning to hike alone in the 24,000-acre Carlton Reserve wilderness area, near North Port.

North Port police called off their search of the swampy reserve on Monday after "exhausting all avenues" to find Laundrie there.

Investigators spent much of Monday searching the Laundrie home, loading cardboard boxes into a van and towing away a silver Ford Mustang.

Petito and Laundrie left her home state of New York in late June or early July, heading west in her white van with plans to visit America's national parks and document the trip on social media.

Laundrie returned home to North Port alone in the van on September 1. Ten days later members of Petito's family reported her missing. Before disappearing, Laundrie had refused to speak with investigators and retained a lawyer.

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Witnesses last saw Petito on August 24 as she left a Salt Lake City hotel. She posted her final photo of the trip on social media the next day. Petito's family believes she was headed to Grand Teton National Park in Wyoming when they last heard from her.

A body was discovered on the edge of that park, in a remote area less than 1,000 feet (300 meters) from where a pair of travel bloggers filmed the white van parked along a dirt road near Spread Creek on the evening of August 27.

An FBI spokesperson has said the body was "consistent" with the 5'5, 110-pound Petito. The autopsy scheduled for Tuesday was expected to identify the remains and determine a cause of death.

In seeking search warrants, investigators have cited an August 27 text purportedly sent by Petito to her mother, Nicole Schmidt, which describes getting repeated calls and voice messages from "Stan," Petito's grandfather.

Schmidt told investigators that message was odd because the young woman would not usually refer to her grandfather by his first name. Petito's family has said a second text message also seemed suspicious.

Last week, police in Moab, Utah, released body camera footage of an August 12 encounter that two of their officers had with Petito and Laundrie during a traffic stop.

Petito sobs in the video as she describes a quarrel with Laundrie that she says became physical at times. The officers did not detain the couple but insisted they spend that night separately, Petito in the van and Laundrie at a hotel.