The Florida couple were on a cross-country trip from Long Island, New York, to Oregon when Petito stopped communicating with her family somewhere in Wyoming in late August. Laundrie returned to their home in the Gulf Coast town of North Port with her 2012 white Ford Transit van on Sept. 1 -- 10 days before Petito's family reported her missing.
TIMELINE: What happened to Gabby Petito?
Utah police incident
As details unfurled surrounding Petito's disappearance, the Moab City Police Department in Utah confirmed an Aug. 12 "incident involving Brian Laundrie and Gabrielle Petito," but there "insufficient evidence existed to justify criminal charges."
Officers responded to a report of a domestic problem after a witness said the couple, involved in an altercation at the Arches National Park, drove off in a white van, according to a police report.
When police officers located a van and pulled it over for a traffic stop, the couple admitted to arguing. Petito admitted that she had slapped Laundrie when she thought her fiance was going to leave her in Moab, according to the report. The couple also stated to police that Laundrie did not hit Petito.
Petito told police that she suffers from severe anxiety and other medical conditions, which were redacted from the police report, and that the arguments had been building for the past few days. Police labeled the incident as a "mental/emotional break" rather than a domestic assault, according to the report.
They agreed to separate for the night and police helped Laundrie get a hotel room while Petito took possession of the van. According to police, the couple did not wish to separate, but officers required them to do so in lieu of no charges being filed. A responding officer deemed Brian to be "at low risk of danger or harm as a result of his proximity to his fiancé."
It's not clear what happened next.
Latest on Petito case Wednesday September 15, 11:30am. Please use 1-800 CALLFBI pic.twitter.com/NpkUEjoME5— North Port Police (@NorthPortPolice) September 15, 2021
Police are "actively looking" into any connection between Petito's disappearance and the murders of Crystal Turner and Kylen Schulte, a couple who was last seen alive in Moab on Aug. 13, the day after Petito's police incident. The bodies of the newlyweds were found at a nearby campsite a few days later, according to KTVX. Both had suffered gunshot wounds.
The FBI is also involved in the double-homicide.
Laundrie allegedly hindering the investigation
Police in the couple's Florida hometown said Laundrie has not cooperated with police and is now considered a person of interest in the case. He has not been charged with any crime.
Laundrie has not made himself available to be interviewed by investigators or provided any helpful details, officials said.
"We are pleading with anyone, including Brian, to share information with us on her whereabouts in the past few weeks," North Port police Chief Todd Garrison said in a statement Wednesday. "The lack of information from Brian is hindering this investigation. The answers will eventually come out."
The FBI and the Suffolk County Police Department in New York are assisting in the investigation.
He reportedly drove back to Florida alone 10 days before Petito was reported missing, and the events leading up to that are presently unknown. That van has since been impounded by investigators and processed for clues.
While Laundrie has not spoken publicly, his family released a statement Tuesday through their attorney Steven P. Bertolino, describing Petito's disappearance as "an extremely difficult time" for both families.
"This is understandably an extremely difficult time for both the Petito family and the Laundrie family," the statement read. "It is our understanding that a search has been organized for Miss Petito in or near Grand Teton National Park in Wyoming. On behalf of the Laundrie family, it is our hope that the search for Miss Petito is successful and that Miss Petito is re-united with her family. On the advice of counsel, the Laundrie family is remaining in the background at this juncture and will have no further comment."
Petito's family penned an emotional letter to the Laundries Thursday begging for information.
The letter reads as follows:
Christopher and Roberta Laundrie,
We are writing this letter to ask you to help find our beautiful daughter. We understand you are going through a difficult time a your instinct to protect your son is strong. We ask you to put yourselves in our shoes. We haven't been able to sleep or eat and our lives are falling apart.
We believe you know the location where Brian left Gabby. We beg you to tell us. As a parent, how could you let us go through this pain and not help us. As a parent, how could you put Gabby's younger brothers and sisters through this.
Gabby lived with you for over a year. She was going to be your daughter in law. How can you keep her location hidden? You were both at Jim and Nichole's house. You were both so happy that Brian and Gabby got engaged and were planning to spend their lives together. Please, if you or your family has any decency left, please tell us where Gabby is located. Tell us if we are even looking in the right place.
All we want is Gabby to come home. Please help us make that happen.
The family also released a statement Tuesday claiming that "the one person that can help find Gabby refuses to help," adding that they "beg the Laundrie family to not 'remain in the background' but to help find who Brian referred to as the love of his life."
"Brian is refusing to tell Gabby's family where he last saw her," the Petito family said. "Brian is also refusing to explain why he left Gabby all alone and drove her van to Florida. These are critical questions that require immediate answers."
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Petito's mother, Nichole Schmidt, said the last video chat she had with her daughter was Aug. 24 or 25, though they exchanged text messages for a few days following.
She has since said she is unsure if it was her daughter actually sending those texts.
"We don't eat, we don't sleep, we're just actively looking for her," she said.
Prior to the last communication, Petito is believed to have been in Grand Teton National Park in Wyoming. She was reported missing to the Suffolk County Police Department by her family on Sept. 11 at approximately 6:55 p.m.
The couple had been documenting their trip on YouTube. They set out on their journey in July from Petito's hometown of Blue Point, New York, saying on social media accounts they intended to reach Oregon by Halloween.
Petito and Laundrie were childhood sweethearts in Suffolk County.
"We were excited for them," Schmidt said. "I believe she's in danger because she's not in touch with us. She could be alone somewhere. She could be stranded somewhere in the wilderness and she needs help."
An eight-minute YouTube video titled "Van Life: Beginning our Van Life Journey" features scenes from the couple's trip.
"Gabby Petito, never goes outside," she says while walking with Brian along a beach. The video, set to music, has nearly 450,000 views: Sunsets. Gabby driving the white van. Gabby running along the beach. Gabby preparing food. Other images show the couple sharing kisses, flipping backward on swings and cartwheeling on the beach.
"I love the van," she says near the end of the video as the camera pans to the white Ford parked in the Utah desert.
The entry is the only one posted on their YouTube channel, Nomadic Statik.
"Thank you so much for watching, and we hope you tag along on our journey wherever the van takes us!" they wrote.
Instagram account mysteriously deleted
Earlier Wednesday, Petito's family said her Instagram account was mysteriously deleted.
"We have no idea who deleted Gabby's Instagram account," the family's attorney told our sister station WABC-TV. "We contacted Instagram and the FBI to let them know that it was deleted."
Facebook said Wednesday that Petito's Instagram account was removed in error and has since been reinstated.
Petito is described as a white female, approximately 5-foot-5 and 110 pounds.
She has blonde hair, blue eyes, and several tattoos, including one on her finger and one on her forearm that reads, "let it be."
Detectives are asking anyone with information on Petito's disappearance to contact Crime Stoppers at 1-800-220-TIPS, and the North Port Police Department is actively assisting in this case and can be reached at 941-429-7382."
In addition, the FBI Tampa Field Office is assisting with this investigation. Tips can also be called into 1-800-CALL-FBI or submitted to Tips.FBI.gov.
The Associated Press and ABC News contributed to this report.