Brian's remains were found Wednesday at the Carlton Reserve in North Port, FL ... only hours after the FBI uncovered some of Brian's belongings during an initial search at the Myakkahatchee Creek Environmental Park.

The Laundrie family attorney tells TMZ, "Chris and Roberta Laundrie have been informed that the remains found yesterday in the reserve are indeed Brian’s. We have no further comment at this time and we ask that you respect the Laundrie’s privacy at this time."

As we reported ... Brian's parents led the FBI to the previously unexplored trail, where the feds found some articles of clothing and a backpack they believed might belong to Brian. The Medical Examiner went to the location, as well as the Pasco County Sheriff's Office's Human Remains Detection Team and a K-9.

The news comes about a month after authorities said the body they found in Wyoming's Grand Teton National Park was indeed Gabby's body. The Teton County Coroner conducted an autopsy and ruled her death a homicide, with authorities saying she was strangled to death.

As you know by now ... Laundrie went on the run and had so far eluded the FBI and Dog the Bounty Hunter during a nationwide manhunt.

The Petito case, of course, gained national attention after Brian returned to his Florida home without Gabby on September 1 ... despite the fact they had taken a cross-country trip together and documented the trip on social media.

Adding fuel to the fire ... there had also been an alleged domestic disturbance while on the road in Utah and a public blowout in Wyoming that got so bad they were booted from a restaurant.

Gabby's parents said they had not heard from her since August 25 and they reported her missing on Sept. 11. Laundrie was named a person of interest just 4 days later but then came a huge twist -- he did not cooperate with authorities and his family reported him missing on Sept. 17 ... adding that they had not seen him in days.

Gabby's family called for Laundrie to turn himself in during an emotional news conference in her home state of NY.

Along the way, there were tons of alleged Brian sightings ... all over Florida and even as far as Canada. Someone alerted authorities they spotted a man on their trail camera that fit Brian's description ... albeit around 450 miles away from his North Port home -- which would be quite a journey on foot over 4 days.

The Okaloosa Co. Sheriff later said they searched the area where the image was taken but didn't find anything, or anyone, of interest. The FBI also paid Laundrie's parent's home a visit to collect some of his items for DNA matching.

Then there was this ... Dog joined the manhunt too, and he even alerted cops about a possible lead.