As the search continues to try and locate Brian Laundrie, who remains a person of interest in the strangulation death of his former girlfriend Gabby Petito, experts are pointing to an explosive fight in a Wyoming restaurant as the key to determining what exactly unfolded between the last time the 22-year-old was seen alive and her death.

In an interview with Fox News Digital, Dr. Ann Wolbert Burgess, who pioneered the FBI’s Behavioral Science Unit, revealed that the fight at Merry Piglets in Jackson Hole, Wyoming, which took place on Aug. 27, could be the key to determining not only when Petito was killed, but also what happened — and if Laundrie was responsible for her death, what exactly happened between the pair.

“The restaurant incident ... is the second and most important,” Burgess said, noting the couple’s now infamous traffic stop in Moab, Utah, on Aug. 12 was the other big event that raised red flags about the pair. “How she has to apologize for his behavior is something that’s kind of characteristic, and this probably enrages him even more because he wants to appear in a certain way.”

Witnesses of the encounter at the restaurant earlier recounted the incident, which involved Laundrie and restaurant staff, with Nina Celie Angelo, a photographer who was present, telling Fox News that Laundrie has “aggressive” body language and left and returned about four times during the encounter. Petito was also seen coming inside at one point and apologizing for Laundrie’s behavior, which Burgess believes could have set Laundrie off.

The Teton County coroner, Brent Blue, announced this week that Petitio’s cause of death, which had been ruled a homicide, was due to strangulation, and that she likely died three to four weeks prior to her remains being discovered on Sept. 19. As such, her date of death is believed to be between Aug. 27 and Aug. 30, which aligns not only with the day of the encounter at the restaurant but also with the last time she had contact with her family, who reported her missing on Sept. 11.

Laundrie, who was reported missing by his parents on Sept. 17, is still being sought by authorities as a person of interest in Petito’s death, and the Carlton Reserve in Florida remains an area of focus, though there have been many who believe that Laundrie isn’t there.

The FBI has issued an arrest warrant for Laundrie for bank card fraud, alleging he used a Capital One card and pin which belonged to an unidentified person and charged over $1,000 between Aug. 30 and Sept. 1.

Gabby Petito, shown here on a police bodycam in Utah, was strangled to death, a coroner has said Gabby Petito, shown here on a police bodycam in Utah, was strangled to death, a coroner has said Photo: Moab City Police Department / Handout