Suspected human remains, items belonging to Brian Laundrie found in Florida park, FBI says

(CNN) What appears to be human remains and items belonging to Brian Laundrie, including a backpack, have been found in a nature reserve in North Port, Florida, according to FBI Special Agent in Charge Michael McPherson.

The remains were found in an area that has been underwater until recently, he said.

The FBI Tampa's Evidence Response Team is on the scene using "all available forensic resources" to process the area. According to McPherson, it's likely the team will be on the scene for several days.

"I know you have a lot of questions, but we don't have all the answers yet," he said reading a statement for the media.

The discovery comes 37 days after Laundrie, the fiancé of Gabby Petito , was reportedly last seen by his parents.

Laundrie's parents, Chris and Roberta Laundrie, informed the FBI and the North Port Police Department Tuesday night that they intended to come to the park on Wednesday morning to search for him, family attorney Steven Bertolino said. Law enforcement met them there Wednesday morning, he said.

After a "brief search" off a trail Laundrie frequented, the family and law enforcement found "some articles" belonging to him, Bertolino said. He would not give any further information on what or how many items were found.

Bertolino said that law enforcement is now conducting a more thorough investigation of that area.

The Myakkahatchee Creek Environmental Park is on 160 acres of heavily wooded land in North Port, Florida, with trails and a camping area. The park connects to the Carlton Reserve, a 25,000-acre nature reserve that has been the primary search location for investigators.

How we got here

Petito, 22, and Laundrie, 23, traveled around the western US in a white van this summer, all while regularly posting photos and stories to their social media pages. Those posts abruptly stopped in late August, though, and Laundrie then returned by himself to their home in North Point, Florida, where they lived with his parents, on September 1.

Petito's family, unable to get in contact with her, reported her missing 10 days later, launching a national search. Laundrie declined to cooperate with the investigation into her whereabouts, and soon after, he also went missing. His family told investigators they believed he had gone to a sprawling nature reserve nearby.

"We believe this was strangling by a human being," Blue told CNN's Anderson Cooper.

Though their social media posts appear idyllic, their relationship was full of tension and conflict in recent months. Petito called her mom regularly, and those conversations appeared to reveal there was "more and more tension" in Petito's relationship, according to a police affidavit for a search warrant of an external hard drive found in the couple's van.

In a report from Moab police, another witness told police he saw the couple arguing over a phone. The witness said that when Laundrie got into the van, Petito appeared to hit him in the arm and then climbed through the driver's side door as if he had locked her out, the report states.

After interviewing Petito, Laundrie and the witness, the officers describe the incident as an argument that turned into a physical fight involving pushing and scratching.