CHICAGO (NewsNation Now) — A man who has basically made his life’s passion and work finding people who don’t want to be found is joining the manhunt for the boyfriend wanted for questioning in the disappearance of 22-year-old Gabby Petito.

“I’m saddling up to catch this dirtbag,” John Walsh, host of “In Pursuit With John Walsh” on Investigation Discovery, told NewsNation’s Ashleigh Banfield.

Petito’s body was believed to be discovered over the weekend at a national park in Wyoming months after the couple set out on a cross-country road trip.

“This is a homicide,” Walsh said. “This dirtbag is out there. I don’t know how he got out of the house with the FBI and local local cops watching him day and night.”

In just three seasons of his show, Walsh has helped capture 26 fugitives and find eight missing children.

Petito’s boyfriend, Brian Laundrie, is not officially a fugitive. He has been named a person of interest in the case, but his whereabouts in recent days were unknown. Laundrie was reported missing Friday after his family said they last saw him Tuesday while wearing a hiking bag with a waist strap heading into Carlton Reserve.

“You know what they did? They bought their son four extra days,” Walsh said. “They bought him four days to get a head start. So this Wednesday night, I’m going to focus in on Brian, he’s going to be the top of the show on ‘In Pursuit.'”

FBI agents and police Monday searched Laundrie’s home. He and Petito had been living with his parents at the North Port home before the road trip on which she apparently died.

The FBI gave no details on the search by at least a dozen law enforcement officers, but agents removed several boxes and towed away a car that neighbors said was typically used by 23-year-old Brian Laundrie’s mother. Local media said Laundrie’s parents were seen getting into a police vehicle.

Walsh calls them the “dirty Laundries.”

“At some point these parents are going to have to pay,” Walsh said. “They’re going to have to pay for being an accessory for putting him on the run.”

Earlier Monday, authorities said they have no plans to conduct a “major search” of the Florida reserve where Laundrie’s parents said he was headed when last seen.

“At this time, we currently believe we have exhausted all avenues in searching of the grounds there,” North Port police PIO Josh Taylor said in a statement to NewsNation affiliate WFLA. “Law enforcement agencies continue to search for Brian Laundrie.”

Walsh says anyone who has information about Laundrie can call him with a tip at 833-378-7783. Callers can remain anonymous.

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