An expert in missing persons cases believes fugitive Brian Laundrie, who is wanted for questioning over the murder of his partner Gabby Petito, may have fled Florida - and had help to do so.
The 23-year-old was named as a person of interest after returning home alone from the couple’s cross-country van trip on September 1.
Laundrie refused to speak with investigators despite not being accused of any wrongdoing.
The 23-year-old vanished just days before Ms Petito’s body was found at a national park in the US state of Wyoming on September 19, sparking a large-scale FBI-led manhunt.
A warrant has also been issued for his arrest in relation to misuse of a debit card.
Expert believes search focus is wrong
Authorities have so far focused on searching a sprawling wildlife reserve in Florida where his parents say he went for a hike.
Brian's father, Christopher Laundrie, has been asked to assist law enforcement with the search at Carlton Reserve, according to the lawyer representing the Laundrie family, Steve Bertolino.
But a former FBI agent Bryanna Fox said their efforts may be wasted.
"It seems unlikely that he's still in that reserve. They did not find any trace of him so far. It's been weeks," he said.
Mr Fox’s theory is he may have had financial or transportation assistance eluding authorities, adding that if someone picked him up hitchhiking or if he boarded a bus, witnesses probably would have gone to police or the media.
"The idea that nothing has been said reinforces to me that he was likely getting help," Fox told NBC News.
"Obviously, that person would have to be very loyal and very close to him ... to not compromise his identity."
Mr Fox also warned the unforgiving terrain and the weather could easily erase any evidence of Mr Laundrie's presence.
"These factors that are here in Florida, a subtropical environment, are known to degrade evidence," she said. "Imagine a massive landscape that's extremely dangerous. There are snakes, gators and animals. There is rain, torrential downpours that come down out of the blue. It's hot."
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