Dog the Bounty Hunter at the Laundrie house in Florida.
Reality TV star Dog the Bounty Hunter has joined the search efforts for Brian Laundrie, a person of interest in the case surrounding Gabby Petito's murder.
Laundrie, 23, the boyfriend of Petito, has been missing since September 15, after he told his parents he was going hiking in the nearby Carlton Reserve. His parents revealed to police three days later that he had not returned.
Laundrie embarked on a road trip with his fiance, Petito, 22, who was last seen alive on August 25.
Petito was reported missing on September 11 by her parents after she did not respond to calls and texts for several days while the couple visited parks in the West.
Her body was discovered in the vicinity of a remote, undeveloped campground along the border of Grand Teton National Park in northwestern Wyoming.
In footage posted on social media, Dog the Bounty Hunter, the former bail bondsman - real name Duane Chapman, 68 - is seen visiting the house of Laundrie's parents Christopher and Roberta on Saturday afternoon.
Dressed head to toe in black, Chapman marches up the drive and bangs repeatedly on their front door.
"I need to speak to the father," Chapman says, before banging on the door of the North Port, Florida property. "I need to ask him where his son is. Is he in there?"
Asked if he was confident of solving the mystery of missing Laundrie's whereabouts, Chapman replied: "Yes - I will find him."
He added: "I'm chasing several leads. We've got a lot of leads. I can't tell you more but we are getting leads every 10 minutes."
Chapman has given himself a six-week deadline to find the fugitive.
He also revealed that he has also set up a special phone line - 833-TELL-DOG - for the public to call his team with tips and leads.
Chapman is volunteering his services, according to the Daily Mail, because he was moved to help Gabby's family, his representative said.
One source said Chapman was interested in a lead from Petito's best friend, Rose Davis, who suggested Laundrie had spent long periods living alone in the Appalachian mountains.
"Unless there is convincing evidence that he's in the swamp in Florida that we don't know about, Dog does not think he's in there," the source said. "He thinks he will stick to what he knows, namely the Appalachians. That's where he knows he can survive for long periods because he's done it before.
"He doesn't think Brian would have the guts to kill himself. He's doesn't seem the violent type."
Chapman starred in reality TV show Dog the Bounty Hunter and gained recognition after the capture of Max Factor heir Andrew Luster in 2003.