'Don't add up': 'Strange' behaviour of Brian Laundrie's parents during search

A bizarre detail about the police search that unearthed potential human remains and items belonging to Brian Laundrie on Wednesday has raised eyebrows.

The remains, and a notebook and backpack belonging to the 23-year-old, who is a person of interest in his fiancée Gabby Petito’s murder, were discovered at a Florida wilderness park in an area that had previously been underwater, the FBI said.

Helicopter footage from WFLA 8 shows a tent erected among trees in the Myakkahatchee Creek Environmental Park which neighbours Carlton Reserve, where Mr Laundrie’s parents said he had gone when he went missing more than a month ago.

The remains have not been identified and are now undergoing forensic examination, Michael McPherson, chief of the Tampa FBI office, said at a news conference.

The shock discovery is the latest twist in a case that has captured the world’s attention.

However, the new evidence is not the only detail about the recent police search that has come under speculation.

Parents involved in search following weeks of silence

It has been revealed that Mr Laundrie’s parents, Chris and Roberta Laundrie, took part in the search on Wednesday with the FBI and police from North Port, Florida.

Video footage of the couple at the scene has been published by Fox News. It shows Roberta appearing to wipe a tear away from her husband's face.

"Chris and Roberta Laundrie went to the Myakkahatchee Creek Environmental Park this morning to search for Brian," the family’s attorney, Steven Bertolino, said in a statement, according to ABC7.

"The FBI and NPPD were informed last night of Brian's parents' intentions and they met Chris and Roberta there this morning.

"After a brief search off a trail that Brian frequented, some articles belonging to Brian were found. As of now law enforcement is conducting a more thorough investigation of that area."

Mr Laundrie and his parents have been heavily criticised for refusing to speak to police after the 23-year-old returned to their Florida home without Ms Petito, 22, on September 1.

• 'Come clean': Brian Laundrie’s sister makes shock claim in TV interview

• Gabby Petito claims her fiancé hit her in new police footage

• 'They were here': Campers 'spot Gabby Petito's fiancé in selfie'

• Seven dead bodies discovered during search for Brian Laundrie

The couple had been on a van road trip around the US when the 22-year-old disappeared and was later found strangled to death.

Former police chief questions if parents had been tipped off

The appearance of Mr Laundrie’s parents during the search on Wednesday has prompted a former police chief to question why they’ve decided to help now.

Former NYPD Chief of Detectives Robert Boyce told ABC7 strange twists and turns cast suspicion over exactly what Chris and Roberta Laundrie knew.

"The day the park reopens, they go into this specific area...they go to this exact spot and they find the backpack," he said.

"They identify the backpack from what I understand, and the notebook in this particular area, so it's quite strange."

The former police chief said there "a lot of things here that don’t add up to coincidence", prompting him to wonder how the items got there and what the parents "knew all along", adding that they may have been tipped off.

"But for them to go to that exact location, it's very, very strange, in that big park ... did they know more, were they holding back? That will be determined in the next couple days I think."

Mr Laundrie is charged in a federal Wyoming indictment with unauthorised use of a debit card, which would allow authorities to arrest him if he is found alive.

It alleges Mr Laundrie used a Capital One Bank card and someone’s personal identification number to make unauthorised withdrawals or charges worth more than US$1,000.

It does not say to whom the card belonged or what type of charges were made but Ms Petito’s parents have claimed it was their daughter’s money.

With AP

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