Gabby Petito's fiancé, Brian Laundrie, vanished 5 weeks ago. He has just been found dead.

On Thursday afternoon, local time, two officers knocked on the door of Chris and Roberta Laundrie's home in North Port, in the US state of Florida.

They spent just two minutes inside, before leaving, refusing to answer questions from the gaggle of reporters crowded on the kerb.

A short time later, the F.B.I. confirmed the long-suspected news. 

The human remains found in nearby Myakkahatchee Creek Environmental Park the previous day belong to the Laundrie's missing son, Brian.

Brian Laundrie: from person of interest, to missing person.

Brian, 23, was a person of interest in the homicide of his 22-year-old fiancée, Gabby Petito, whose body was found in a Wyoming forest in late September. 

A coroner later declared her death to be a homicide caused by strangulation and concluded that she had likely been dead for three to four weeks before her body was found.

Gabby Petito. Image: Instagram.

Gabby's parents had reported her missing on September 11, after Brian returned alone from their cross-country road trip. 

The young couple had earlier decided to "downsize" their lives and travel full time. They transformed the belly of an 11-year-old Ford Transit van into a mobile home, and on July 2 set a course west across America. Their final destination was meant to be Portland, Oregon, which they were due to reach some time in late October. 

However, on September 1, Brian returned to his parents' North Port home. He had the van, but there was no sign of Gabby.

Despite appeals from the aspiring travel influencer's family and police, Brian shed no light on her whereabouts.

He then, too, vanished on September 13, after telling his parents he was setting out on a hike in the Myakkahatchee Creek Environmental Park, sparking a wide-scale search and enormous media attention both in the US and abroad.

The speculation intensified after details emerged in September of an altercation the couple had in Utah on August 12. Body cam footage was released that showed Gabby in a distressed state while being interviewed by police. 

Responding officers concluded that there was no cause for charges. The pair was instead advised to spend the night apart.

Weeks later, Gabby was killed.

Police bodycam footage of Gabby Petito. Image: Moab Police Department.

While Brian Laundrie was named as a person of interest in Gabby's death, he had not been arrested or charged and no formal police interview had taken place.

An arrest warrant was issued for him relating to federal fraud charges, after he allegedly made unauthorised withdrawals or charges worth more than $1,000 using someone else's debit card during the period when Gabby was missing. Authorities have not said to whom the card belonged.

What led authorities to Brian's remains.

Brian Laundrie's remains were discovered on Wednesday morning, local time, after his parents instigated a search of the wilderness reserve.

Authorities were notified of the couple's intentions and joined them to scale the area, which had recently reopened to the public after being underwater.

There, they found a notebook and a backpack which are believed to belong to Brian, along with his skeletal remains.

#UPDATE: On October 21, 2021, a comparison of dental records confirmed that the human remains found at the T. Mabry Carlton, Jr. Memorial Reserve and Myakkahatchee Creek Environmental Park are those of Brian Laundrie. @FBITampa pic.twitter.com/ZnzbXiibTM

— FBI Denver (@FBIDenver) October 21, 2021

According to police, Chris Laundrie was the first to spot an item belonging to his son.

"It's quite sad, you can imagine as a parent, finding your son's belongings alongside some remains. That's got to be heartbreaking. And I can tell you that they are heartbroken," Laundrie family lawyer, Steven Bertolino told CNN.

A lawyer for Gabby's family told Fox News they would make a statement "at the appropriate time and when they are emotionally ready". 

Feature image: YouTube/Nomadic Statik