Authorities said a body discovered in northern Wyoming is believed to be that of 22-year-old Gabrielle “Gabby” Petito, who disappeared while on a cross-country trek with her boyfriend. The FBI said the body of Petito was found Sunday by law enforcement agents who spent the weekend searching camp sites on the eastern border of Grand Teton National Park. FBI Supervisory Special Agent Charles Jones said the cause of death not yet been determined, and the specifics on where and how the body was found were not disclosed. Jones said investigators were still seeking information from anyone who may have seen Petito or Laundrie around camping sites in the area of Spread Creek, where law enforcement search efforts focused over the weekend.

Boyfiend Brian Laundrie, 23, has been identified as a person of interest in the case. He was last seen Tuesday by family members in Florida, and now the subject of an intense search in a Florida nature preserve. More than 50 law enforcement officers on Sunday started a second day of searching for Laundrie at the more than 24,000-acre (9,712-hectare) Carlton Reserve in Sarasota County, Florida, a wildlife area with more than 100 miles (160 kilometers) of trails, as well as campgrounds.

Petito and Laundrie left in July on a cross-country trek in a converted van to visit national parks in the U.S. West. The couple’s trek in the Ford Transit began from Long Island, and they intended to reach Oregon by the end of October, according to their social media accounts. However, Petito vanished after her last known contact with family in late August from Grand Teton National Park in Wyoming. Laundrie was alone when he drove the van back to his parents’ home in North Port, Florida, on Sept. 1, police said. Petito’s family filed a missing persons report Sept. 11 with police in Suffolk County, New York.