Last week, Brian Laundrie was targeted by a federal arrest warrant following his disappearance and fiancee Gabby Petito's murder.

Officially, he was only a "missing person" before that. Now, those searching for him are empowered to arrest him.

Duane "Dog The Bounty Hunter" Chapman has raised eyebrows by joining the manhunt.

When he showed up at the Laundrie family home, the fugitive's mother called the police.

Multiple law enforcement agencies continue their ongoing search for Brian Laundrie.

The 23-year-old was allegedly last seen weeks ago at his parents' home in North Port, Florida.

While the federal warrant for his arrest is not directly for the murder of Gabby Petito, it's not unrelated.

In addition to officials conducting the search, there are literally millions of people on the lookout for Brian.

That's what happens when a disappearance-turned-murder case takes social media and the news cycle by storm.

While most of the civilians looking for Brian are just amateurs keeping an eye out, there are also professionals on the case.

Duane "Dog The Bounty Hunter" Chapman has reportedly received a barrage of tips through his own tip line.

Despite being a reality star known for his sensational, over-the-top appearance and manner, he actually is a professional bounty hunter.

What that says about the system of bounty hunting and criminal justice in our nation ... well, that's another matter.

Early this week, Duane showed up at the Laundrie family home.

This is the house that was previously searched by law enforcement as they executed a warrant.

Ostensibly, Duane is assisting in the search for the family's "missing" son.

Interestingly, Roberta Laundrie called the police on Duane, dialing 911 when he showed up.

"The female, Roberta ... called in on 911," audio recordings reveal that the dispatcher saying.

Apparently the caller, Roberta, "referenced a situation with a male."

However, Duane claims that he actually spoke to law enforcement before he paid a visit to the Laundrie home.

“It’s a shame they wouldn’t speak with us," Duane lamented while speaking to Fox News on Monday.

"The police said we were welcome to knock on the door," he added, "so we did."

His purpose in going there was simple.

"I wanted to tell the Laundries that our goal is to find Brian," Duane shared, "and bring him in alive."

According to police, they handled the call like they would any other.

“We’ve been called to the house numerous times for all sorts of issues: media, protesters, celebrity searchers,” police told Fox News.

“It’s not something normal," they shared.

"If the family calls and is concerned," the local police explained, "we will respond like we would for anyone.”

Meanwhile, Duane has spoken about receiving a high volume of tips on his personal hotline.

According to him, a lot of these tips point to Laundrie being somewhere along the Appalachian trail.

That fits with Brian's known history, as he has apparently camped in that area for months in the past.

Duane shared that he is looking into one tip in particular.

This tip pointed to Brian traveling to a Florida campground that is 75 miles away from the Laundrie house.

Allegedly, he traveled there with his parents in early September ... but they may have left without him.

Duane told Fox News that he has heard that Laundrie's parents spent the night in Fort De Soto Park with their son early this month.

This would have been after Gabby vanished and Brian returned home without explanation.

But before Brian himself disappeared ... and before Gabby's remains were found.

The tip about the campground visit, at least, seemed to check out.

"They were registered, went through the gate. They’re on camera. They were here," Duane confirmed this week.

"We think at least if he’s not here right now, we are sure he was caught on camera as he went in the gate," he said.

Duane says that this means "that he was here for sure. Not over in the swamp."

Fortunately, tips aren't going exclusively to Duane, as law enforcement aircraft were seen in the area of the campground.

"I think he's been here for sure," Duane added.

Upon returning to Florida without his fiancee or any explanation (to the public) for her whereabouts, Brian did two things.

First, he got a lawyer.

Second, he refused to cooperate with any investigators who hoped to find Gabby.

Chris and Roberta Laundrie, his parents, have insisted through their attorney that they do not know their son's whereabouts.

Allegedly, they hope that authorities do find their son, claiming to be "concerned" about him and hope that he is found.

There has been widespread speculation that they in some way assisted their son in disappearing, but they insist that this is untrue.