A search has been suspended in a Florida nature preserve for a man police say is a person of interest in the death of his girlfriend, Gabriel “Gabby” Petito, whose body authorities believe was discovered at a Wyoming national park the couple visited.

North Port Police Department said in a news release that the agency “has no plans to conduct a major search” for Brian Laundrie, 23, on the 24,000-acre Carlton Reserve in Sarasota County.

The police statement said officers had “exhausted all avenues in searching of the grounds there”.

Law enforcement officials at the Carlton Reserve
Law enforcement officials at the Carlton Reserve (North Port Police Department/AP)

It was not immediately clear if investigators were searching elsewhere for Laundrie.

Investigators focused over the weekend on the wildlife area after his parents told police he may have gone there last week.

The reserve has more than 100 miles of trails and numerous campgrounds.

In Wyoming, the FBI announced on Sunday that a body discovered in northern Wyoming was believed to be that of 22-year-old Ms Petito. It was found by agents searching campsites on the eastern border of Grand Teton National Park.

Brian Laundrie
Brian Laundrie (Moab Police Department/AP)

The cause of death not yet been determined, said FBI supervisory special agent Charles Jones. Specifics on where and how the body was found were not disclosed.

“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.”

Ms 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”.

A lawyer acting as a spokesman for the family asked in a statement that they be given room to grieve.

Richard Benson Stafford indicated the family would make a public statement at a later date, and thanked officials with the FBI, Grand Teton Search and Rescue and other agencies that participated in the search.

“The family and I will be forever grateful,” Mr Stafford said.

Gabrielle Petito talking to a police officer
Gabrielle Petito talking to a police officer (Moab Police Department/AP)

An undeveloped camping area on the east side of Grand Teton bordering national forest land will remain closed until further notice while the investigation continues, Mr Jones said.

He said investigators were still seeking information from anyone who may have seen Mr Petito or Laundrie around camping sites in the area of Spread Creek, where law enforcement search efforts focused over the weekend.

The pair left in July on a cross-country trek in a converted van to visit national parks in the US West.

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

Ms Petito’s family filed a missing persons report on September 11 with police in Suffolk County, New York. They had been pleading for the Laundrie family to tell them where their son last saw her.

The couple were childhood sweethearts who met while growing up on Long Island, New York. His parents later moved to North Port, about 35 miles south of Sarasota.

The couple’s trek in the Ford Transit began in July from Long Island. They intended to reach Oregon by the end of October, according to their social media accounts, but Ms Petito vanished after her last known contact with family in late August from Grand Teton National Park, authorities said.