Brian Laundrie's father breaks cover for the first time since FBI raid at his ...

Brian Laundrie's father Christopher Laundrie broke cover for the first time Tuesday - but refused to answer questions about his missing son.

The 62-year-old is seen in exclusive DailyMail.com photos walking out onto his driveway around 3pm, a day after the FBI raid on the North Port, Florida home he shares with wife Roberta.

Dressed in khaki shorts and a black top, Laundrie strode out to his red Dodge Ram pick-up truck and drove past the continued police presence outside his home.  

He returned 20 minutes later with half a gallon of milk and quickly disappeared back into the house. 

The Laundrie residence has become somewhat of a media circus since Brian returned home alone September 1 from a cross-country trip with fiancée Gabby, 22, who was reported missing 10 days later. Her body was found in a remote area of Grand Teton National Park in Wyoming on Sunday. 

On Tuesday, the Teton County Coroner confirmed that the remains are those of Gabby Petito, with the manner of death ruled a homicide. The cause of death remains pending final autopsy results.  

The missing person case took a bizarre turn last week after Brian, who has refused to cooperate with authorities in the investigation, also vanished. 

The search for the 23-year-old entered its fifth day on Tuesday, with Florida Governor Ron DeSantis ordering all state agencies to assist in the manhunt as local police deployed ATVs and drones to a snake and alligator-infested swampland in the Carlton Reserve where Brian was last reported to be.  

DailyMail.com has learned cops have also been searching farmland in northern Florida - more than 250 miles from the FBI-led hunt at the nature reserve.

They sprang into action after a reported possible 'sighting' of Brian Laundrie in footage from a camera set up to spot deer near the town of Baker.

Local law enforcement conducted a detailed ground search and also used drones, but did not find any evidence to suggest the unknown man on the video was Laundrie.

The video was posted on Facebook by user Sam Bass who said it was shot at 6:17am Monday. 

'I'm not saying this is the guy but whoever was on my trail camera this morning… strongly fits the description of Brian Laundrie. Authorities have been contacted but people in the North West Florida area need to be on the lookout,' he wrote in a post. 

Okaloosa County Sheriff's Office information officer Michele Nicholson told DailyMail.com: 'Investigators went out and did an extensive ground search of that entire area which is very rural.

'They also searched surrounding farmlands and fields and used a drone. However, they didn't find anything of note. There was no evidence of Laundrie being there. Meanwhile, there have been reports in the past of an individual of that appearance in the area before.'

Nicholson added: 'Officers are no longer actively searching. Also, there is nothing that we heard that would indicate he could be in this area. We have checked and there is no reason to believe he has any specific connections up here – family members, friends etc.' 

She said her department did liaise with investigating authorities in North Port, Florida, where the Laundries live and the current location of the massive search operation. 

Earlier on Tuesday North Port Police announced its officers had returned to the 'vast and unforgiving' 25,000-acre Carlton Reserve to continue the search that morning in the waist-deep water and 'dangerous' terrain.

More than 50 searchers from at least eight law enforcement agencies led by the FBI are using huge swamp-busting amphibious vehicles, ATVs, bloodhounds, other K9s and drones as they ramp up efforts to track down the 23-year-old. 

Gov. DeSantis later announced that at the request of local law enforcement, he had 'directed all state agencies under my purview to continue to assist federal & local enforcement as they continue to search - we need justice for Gabby'.  

Laundrie went missing a week ago on Tuesday, September 14, with his parents only reporting his disappearance on Friday. 

Cops released a video of the search today showing teams in tactical gear being briefed, K9 sniffer dogs in action, specialist vehicles traversing swampland and drone footage of the massive area being searched.

North Port Police also emphasized they are involved in a criminal probe now, which is being led by the FBI and they are 'assisting out federal partner in any way we can to bring this investigation to a close'.

Commander Joe Fussell (correct), from the local department, said on the video: 'The terrain is very difficult. Essentially 75 per cent of it is under water.

'And other areas that are dry, we're trying to clear. So we're expecting to get wet by the end of the day and check the entire area for Brian Laundrie.'

He also revealed the searchers 'have multiple drone operators that have been sent out in numerous teams.

'We also have drones that operate as higher altitude that has more advanced technology to zoom in and to see areas that are difficult to access on foot or in wheeled vehicles as well.'

Two huge high-water all-terrain vehicles came out of one area briefly and headed along a perimeter road to make for another location in the reserve. They carried at seven searchers. 

Police had halted the large-scale operation Monday after a weekend of combing through the nature reserve, about five miles from the home Laundrie shared with his parents and Petito. 

This came the same day the final resting place of the body believed to belong to Petito was revealed to be marked with a stone cross tribute at the Spread Creek Dispersed Campsite, close to the Grand Teton National Park in Wyoming.

A body matching Petito, 22, was discovered there Sunday bringing her family's hopes of finding her alive to an end.

An autopsy is being carried out today and is expected to confirm the remains belong to Petito - as well as cast light on how she died. 

Petito's family said in a statement released this afternoon that they will speak publicly after her body is returned home. 

Petito was last seen alive August 24 leaving a motel in Salt Lake City in Utah with Laundrie during the cross-country campervan trip that she and Laundrie had set out on back in early July. 

She was then last heard from the next day when she called her mom.

Laundrie arrived back in North Port alone on September 1 in their van and Petito was reported missing September 11 by her family. 

Laundrie refused to cooperate with investigators or tell them when he had last seen his girlfriend and was named a person of interest in her disappearance last Wednesday - four days before a body was discovered.

Laundrie's parents then made the stunning revelation Friday that he too had vanished and that they had not seen him since Tuesday - when he allegedly left their home with a backpack saying he was heading to the reserve. 

On Monday, a dramatic FBI raid was executed on the Laundrie family home and the 23-year-old's silver Ford Mustang convertible was seized by authorities.   

Steven Berolino, an attorney for the family, told ABC7 the family went looking for Laundrie on Wednesday and found the Mustang, which had a police note on it demanding that the vehicle be removed from the area.

The family initially left the car there so Laundrie could drive it back, but they returned on Thursday to retrieve it, according to Bertolino.  

North Port Police Public Information Officer Josh Taylor said Tuesday morning search teams were up against the elements as they returned to the nature reserve to continue the 'dangerous work' to track down Laundrie.

Taylor said heavy rains the day before has left much of the swampland 'waist-deep in water'.

'Carlton Reserve is a vast and unforgiving location at times. It is currently waist-deep in water in many areas,' he said. 

'This is dangerous work for the search crews as they are wading through gator and snake infested swamps and flooded hiking and biking trails.' 

As well as local police and the FBI, other agencies involved in the search include Florida Wildlife Commission, Sarasota County Sheriff's Office, Lee County Sheriff's Office, Charlotte County Sheriff's Office, Sarasota Police Department and Venice Police Department.

The search began on Saturday, starting at the Myakkahatchee Creek Environmental Park which is linked to the Carlton Reserve. 

But the focus has now switched to covering the area closer to the city of Venice, along with adjoining lands, said Taylor. 

It is not clear whether authorities have receive intel directing them to this part of the reserve. 

'A weekend ground search and aerial search Monday of the 25,000-acre preserve has yet to yield any answers, but we must press on,' said Taylor. 

North Port Police tweeted photos of searchers assembling for a briefing early Tuesday, announcing the efforts are: 'By land. By air.'

Photos show teams driving buggies through dense foliage and police officers using remotes to operate drones going up into the air.

Dozens of law enforcement vehicles were also seen at the entrance to the nature reserve.