After searching for more than a month, authorities found the skeletal remains of Brian Laundrie - who was a person of interest in the disappearance of his fiancée, Gabby Petito - and the break in the case came from his parents.
Investigators located partial human remains Wednesday at the Carlton Reserve, a sprawling Florida wildlife refuge that was Laundrie's last known location. The remains were identified as the 23-year-old man through dental records, the FBI field office in Denver announced Thursday.
This came after Laundrie's parents directed FBI agents and North Port police to an area where "some articles belonging to Brian were found," according to a statement Wednesday by Laundrie's family's attorney Steven Bertolino. He said the Laundries found the items "in an area where they had initially advised law enforcement that Brian may be."
A senior law enforcement source told NBC News that the remains were found near a backpack that may have belonged to Laundrie. Other items thought to have belonged to Laundrie, including a notebook, "were found in an area that up until recently had been under water," Michael McPherson, special agent in charge of the FBI's Tampa office, said.
"Chris and Roberta will wait for the forensic identification of the human remains before making additional comments," Bertolino said Wednesday when asked about possible cooperation between his clients and authorities.
David Thomas, who worked for 20 years as a police officer in Michigan and Florida, said it's likely that Laundrie's parents made the decision to involve themselves publicly in the search with the direction of their attorney.
"If you're smart, you let your attorney do the talking. You don't do it. And they lawyered up right away," Thomas, a professor of forensic studies at Florida Gulf Coast University, said.
"I would suspect that any move that they made, like when the dad went out and helped them with the search … anything you see them do, I don't think they would do that without the advice of their attorney."
Laundrie's parents have said that speculation they helped their son escape is "just wrong," according to a late September statement from Bertolino.
"Chris and Roberta Laundrie do not know where Brian is," Bertolino said. "They are concerned about Brian and hope the FBI can locate him. The speculation by the public and some in the press that the parents assisted Brian in leaving the family home or in avoiding arrest on a warrant that was issued after Brian had already been missing for several days is just wrong."
Former FBI agent Bryanna Fox, an associate professor of criminology at the University of South Florida in Tampa, said Wednesday that prosecuting a charge of aiding and abetting or obstruction of justice is a high bar requiring proof of an "awareness of the illegal act and intent to assist."
Law enforcement officials have not accused the Laundries of wrongdoing.
Retired Lt. Thomas Nolan, a 27-year veteran of the Boston Police Department, said it's "certainly fair to question as to what may have transpired between law enforcement, prosecutors and the parents."
"Authorities do walk a fine line in terms of alienating the parents and receiving no information or cooperation from them whatsoever; it's a delicate balance," he said.
Laundrie, of North Port, Florida, was a "person of interest" in the disappearance of Petito, who was found dead in Wyoming last month.
Petito's body was discovered Sept. 19, at the Spread Creek Dispersed Camping Area in Bridger-Teton National Forest in Wyoming, and a coroner ruled the 22-year-old woman's death a homicide by "manual strangulation."
Petito and Laundrie were on a cross-country road trip, chronicling their travels on social media, before he returned to his parents' home in North Port, Florida, on Sept. 1 without his fiancée, police said.
Laundrie's parents have kept a low profile ever since, telling investigators their son went hiking two weeks later and never returned, sparking a national manhunt.
Last weekend, Petito's parents accused the Laundries of withholding crucial information about her death and his mysterious disappearance.
In an interview with "60 Minutes Australia," Petito's mother, Nicole Schmidt, called out the Florida couple who were set to become her daughter's in-laws.
"I think silence speaks volumes. I believe they know probably, if not everything, they know most of the information," Schmidt said. "I would love to just, face to face, ask, 'Why are you doing this? Just tell me the truth.' "
Laundrie's family said he went hiking Sept. 13 in the Carlton Reserve, the 25,000-acre reserve that had been searched multiple times prior to Wednesday's discovery.
Petito's parents have accused the Laundries of not being cooperative when they were searching for their daughter and of withholding information from them after Brian returned home without her.
Joseph L. Giacalone, a retired sergeant with the New York Police Department who supervised a cold case unit in the Bronx, said, "most parents would do exactly what they had to do."
"It may be morally and ethically wrong, but we understand what mothers will do, what fathers will do. I'm sure they expected something strange, when he comes home with the car and she's not around," he said, referencing Laundrie's return without Petito after the road trip.
But because the remains were positively identified as Laundrie, that could complicate the investigation into Petito's death.
Now that authorities identified the remains as Laundrie, Giacalone said he expects the case to end as an "exceptional clearance," meaning that even if police suspect Laundrie killed Petito, the investigation would end.
"Because he's dead, they can't do anything about it," he said, adding that the case could end with an "unfulfilled expectation," especially for Petito's parents, who may never learn exactly what occurred before and after their daughter's death.