The caller can be heard saying that a man, purportedly Laundrie, had been slapping and hitting a woman before the couple drove off in their van, the outlet said citing audio obtained from the Aug. 12 incident.
The news comes one day after the FBI found a body "consistent" with the description of 22-year-old Petito in the Wyoming national park.
Her family had reported her missing on Saturday, Sept. 11. She had been traveling across the country in her van with Laundrie, her fiancé, who returned to Florida without her on Sept. 1 and refused to cooperate with investigators.
Police are searching for Laundrie, who has not been seen in nearly a week, according to his parents.
Bodycam footage previously released by the Moab Police Department that was taken when officers responding to the Sunday, Aug. 12 report showed Petito crying as she told police about the altercation with Laundrie.
Officers wrote in the report that Petito had been the one to slap Laundrie and that no one had reported Laundrie had struck Petito, Fox News said.
Police also said no one was seriously injured and no one wanted to press charges.
Police categorized the incident as a "mental/emotional health break," and the couple agreed to separate for the night.
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