New theory about how Gabby Petito's fiance is avoiding police

Searchers have discovered new evidence that suggests the partner of Gabby Petito, 22, and person of interest in her death, Brian Laundrie, may be using a kayak to avoid being found.

The 23-year-old was the fiancé of YouTuber Gabby Petitio, who was found dead at a national park in the US state of Wyoming.

He 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 on September 19, sparking a large-scale FBI-led manhunt in Florida.

A warrant has also been issued for his arrest in relation to misuse of a debit card.

New theory about Brian Laundrie

US TV personality Duane Chapman, known as Dog the Bounty Hunter, has since joined the search for Laundrie, attracting a small army of followers.

Michael Hadsell, president of Peace River K9 Search and Rescue, is among the searchers who joined the former reality star's hunt in Fort De Soto Park, where the Laundrie family camped in early September.

He said he was skeptical of the search at first, but now believed they were on the right track.

“I wasn’t a big believer in the Fort De Soto when it first started,” Mr Hadsell told WSNN-TV News.

"But after working out there... I'm like, 'Wow, we may be really into something'."

The FBI operation has so far focused mainly on a Carlton Reserve, closer to Laundrie’s home, where his parents say he went for a hike. But officials are also looking at Fort De Soto.

Mr Hadsell revealed they found signs Laundrie may be avoiding authorities by kayaking around the Florida park, which is made up of five interconnected islands at the mouth of Tampa Bay.

“We did find some campsites, we did find some evidence of kayaks near the campsites so it is possible that Brian’s out there,” Mr Hadsell said.

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He said Laundrie’s family had refused a request from his K9 team to supply anything with his scent on it.

“The parents as you know are being uncooperative, so we don’t have any sent articles or anything from Brian to be able to use it as a target odour for our dogs to work on,” Mr Hadsell said.

“So, we do what we call, 'general human scent'."

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