Fox News reported that Nina Celie Angelo, of New Orleans, reported that she and her boyfriend, Matthew England, were at Merry Piglets, a restaurant in Jackson Hole, on Friday, Aug. 27, when they saw Laundrie arguing with staff.
Angelo told the news outlet that she believed Laundrie was arguing with the employees about money or the bill.
England told the news station the Petito seemed "visibly upset" by the incident, and Angelo said the 22-year-old Long Island woman later came in and apologized for Laundrie's behavior.
Laundrie and Petito, who both grew up in the hamlet of Blue Point in Suffolk County, had been traveling across the country together in Petito's van.
Laundrie returned to his parents' home in Florida without Petito on Wednesday, Sept. 1.
Petito's parents reported her missing on Saturday, Sept. 11, and her remains were found in a Wyoming national park on Sunday, Sept. 19.
The Teton County coroner's initial determination for Petito's manner of death is homicide. The cause of death has not yet been released pending final autopsy results.
Authorities have named Laundrie a person of interest in Petito's death, and they have been searching for him since his parents reported he hasn't been seen since Tuesday, Sept. 14.
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