A BODY DISCOVERED in a national park in Wyoming is believed to be that of 22-year-old Gabrielle Petito – while her partner is now subject of an intense search in Florida.

The FBI said the body was found on Sunday by law enforcement agents who spent the weekend searching campsites on the eastern border of Grand Teton National Park.

The cause of death has not yet been determined said FBI Supervisory Special Agent Charles Jones.

“Full forensic identification has not been completed to confirm 100% that we found Gabby, but her family has been notified,” Mr Jones said. “This is an incredibly difficult time for (Petito’s) family and friends.”

Boyfriend Brian Laundrie, 23, has been identified as a person of interest in the case. He was last seen on Tuesday by family members in Florida.

💔#GABBYPETITO she touched the world. pic.twitter.com/DukH7UCTPo

— joseph petito (@josephpetito) September 19, 2021

The pair, childhood sweethearts who met while growing up on Long Island, New York, left in July on a cross-country trek in a converted van to visit national parks in the west of the US.

The couple’s trek in the Ford Transit began in July from Long Island and they intended to reach Oregon by the end of October, according to their social media accounts.

But Petito vanished after her last known contact with family in late August from Grand Teton National Park in Wyoming, authorities said.

Laundrie was alone when he drove the van back to his parent’s home in North Port, Florida, on 1 September, police added.

Petito’s father, Joseph, posted on social media an image of a broken heart above a picture of his daughter with a message that said, “she touched the world”.

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.

Meanwhile, more than 50 officers started a second day of searching for Laundrie yesterday at the more than 24,000-acre Carlton Reserve in Sarasota County, Florida, a wildlife area with more than 100 miles of trails, as well as campgrounds.

Police in North Port, Florida, said in a statement that they were heartbroken to learn of the discovery of the body and pledged to continue searching for answers in the case.

Petito’s family had been pleading for the Laundrie family to tell them where their son last saw her.