'I'll find him': Dog the Bounty Hunter joins search for Gabby Petito's fiancé

Dog the Bounty Hunter has joined in the search to find Brian Laundrie.

Brian Laundrie, 23, was the fiancé of YouTube blogger Gabby Petitio, 22, who was found dead at a national park in Wyoming, US, this week after the couple's cross-country van trip.

Mr Laundrie has a warrant issued for his arrest in relation to misuse of a debit card. He was reported missing on September 17 after returning to the couple's Florida home alone on September 1 — five days after Ms Petito was last seen.

Mr Laundrie also remains a person of interest in Ms Petito’s disappearance.

This weekend, reality TV show star Duane Chapman, also known as Dog the Bounty Hunter, appears to have joined in the search for the 23-year-old.

Brian Christopher Laundrie pictured with his fiancee Gabrielle 'Gabby' Petito.
Brian Laundrie seen with Gabby Petito. Source: AAP

He was seen on Saturday (local time) knocking on a door at the Laundrie residence but no one answered, WFLA reported.

When he was asked what he was doing there, he answered: "Come on, you know".

Chapman told Mail Online: "I will find him".

He told the publication he has leads and wanted to speak with Mr Laundrie's dad. He then implored people who had information to call him.

Chapman’s appearance shows just how invested people are in the case of Ms Petito’s death, which has captured attention across the globe.

Dog the Bounty Hunter knocks on a door at the Laundrie residence.
Dog the Bounty Hunter visits the Laundrie residence. Source: WFLA

Police have combed the Carlton Reserve near Mr Laundrie’s family home for days but so far have turned up nothing. His parents told police he had gone there for a hike.

Local media reports he left behind his wallet and phone.

A friend claims if Mr Laundrie had to survive in the wilderness he would be more than capable.

Dog the Bounty Hunter seen at the Laundrie home. Source: WFLA
When he was asked what he was doing there, he answered: "Come on, you know". Source: WFLA

Ms Petito’s death has been deemed a homicide by the FBI, but it is unknown how she died.

On Thursday (local time), Norma Jean Javolec told Fox News she had picked up Mr Laundrie, who was hitchhiking, on August 29 and dropped him off at the Spread Creek camping area where Ms Petito’s remains were found.

She said the pair made small talk before he "freaked out" and tried to get out of her moving car.

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