MOAB, Utah. (WFLA) – The City of Moab will launch an investigation into how police officers handled a domestic dispute last month between Gabby Petito and Brian Laundrie.

Police said the couple was seen arguing and hitting each other, and Petito scratched Laundrie’s face. However, officers believed the situation was more of a mental health crisis instead of a domestic assault.

One of the officers decided to separate the couple that night, with Petito staying in the van and Laundrie in a hotel.

“The Moab City Police Department has clear standards for officer conduct during a possible domestic dispute and our officers are trained to follow those standards and protocol,” the city said in a statement on Thursday. “At this time, the City of Moab is unaware of any breach of Police Department policy during this incident. However, the City will conduct a formal investigation and, based on the results, will take any next steps that may be appropriate.”

Moab City Police Chief Police Chief Bret Edge said an “outside party” requested a formal investigation into how officers handled the Aug. 12 incident between Petito, who later went missing and whose body was found Sunday in Wyoming, and her fiancé, Laundrie, who has been named a person of interest in the case and remains missing.

“In compliance with police department policy, we will conduct an investigation,” Edge said. “The police department will identify an unaffiliated law enforcement agency to conduct the formal investigation on our behalf.”

The chief also added, “should the investigation identify areas for improvement we will take that information to heart, learn from it, and make changes if needed to ensure we are providing the best response and service to our community.”

On Aug. 12, nearly two weeks before Petito’s final social media post, police in Moab received a 911 call reporting a domestic dispute prior to the police responding to the incident between the couple near the Moonflower Community Cooperative. In the call, the witness claimed “the gentlemen was slapping the girl” during the altercation.