The almost hour-long video shows officers from Moab City Police Department separating Ms Petito and Mr Laundrie, who returned from a road trip without the Long Island native about a week ago, prompting an investigation.
He has since been named as a person of interest by police in North Port, Florida, where the pair lived together, and from where their road trip started.
The body camera footage shows officers interviewing Ms Petito and Mr Laundrie, who reportedly fought before a witness called 911 with concerns for the pair. No charges were filed.
It was alleged that she slapped her fiance because she feared he was going to drive off without her following an argument. The incident was classed as a “mental/emotional health break” and not a domestic assault, according to police.
As ABC7 News reported, Ms Petito told officers that arguments between the pair had become more frequent in the days before 12 August, and that she suffers from serious anxiety.
The pair were thought to have separated that night, and continued travelling together the following day.
Ms Petito stopped communicating with her family somewhere in Wyoming, with her mother receiving a final text from the 22-year-old on 30 August, it was reported. A search has been ongoing since 11 September.
Ms Laundrie, who returned without his fiance and has so far refused to cooperate with authorities, was named as a person of interest on Wednesday. He has since faced calls from Ms Petito’s family to help with the search.
Police in North Port are expected to hold a press conference on Thursday to provide an update on its investigation and search for Ms Petito.