An alligator-infested reserve in Florida has been searched by a team of divers, police and FBI agents in the hunt for Brian Laundrie, 23 – Gabby Petito’s missing fiancé.
Boats and helicopters were used to assist the team in the investigation, days after it was launched, as Ms Petito’s body was found on Sunday in a remote corner of the Bridger-Teton National Forest in western Wyoming.
Mr Laundrie has been named as a “person of interest” by authorities.
Despite searching the alligator-infested Carlton Reserve on Wednesday, a spokesman said at nightfall that they had found “nothing” to show for their attempts.
Police are currently searching the more than 24,000-acre wilderness preserve near his home in North Port, Florida.
Carlton Reserve is dominated by swampy water but is also home to more than 80 miles (129km) of hiking trails.
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Sections of the reserve are nearly impassable to hikers, with some parts home to other wild animals such as snakes and deer.
A diver unit, the Sheriff’s Underwater Recovery Force, has been brought in to assist with the search.
“These highly-trained deputies work in the most difficult and challenging environments imaginable,” the sheriff’s office said in a tweet.
Ms Petito, 22, was reported missing on 11 September, and disappeared after she and Mr Laundrie left on a road trip in a converted van to visit national parks in July.
The pair are understood to have got into a fight along the way, and Mr Laundrie was alone when he returned in the van to his parents’ home in early September.
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Video released by police in Utah showed that an officer pulled the couple’s van over on 12 August. The footage showed an upset Ms Petito.
Mr Laundrie was reported missing by his family over the weekend and is understood to have entered the reserve alone on a hike three days earlier.
North Port police said in a statement on Friday: “It is important to note that while Brian is a person of interest in Gabby’s disappearance, he is not wanted for a crime.”
It added the investigation was now a “multiple missing person” case.
It comes after the FBI confirmed human remains found in a national park in northern Wyoming were those of missing Ms Petito.
Her manner of death was homicide but the cause of death was not disclosed pending final autopsy results, officials said on Tuesday.