In an update posted online Tuesday and on social media Wednesday afternoon, the STM said that according to "the preliminary findings of [an] internal investigation," its officers "followed the rules for the use of force taught at the École nationale de police du Québec" during a violent incident at Jean-Talon metro station on April 17.

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A viral video of the incident posted to social media shows two STM officers holding an individual down on the station floor. One officer appears to punch the individual several times.

Editor's Choice: A Video Shows STM Officers Wrestling Someone After They Allegedly Didn't Pay Metro Fare

Several reports have identified the individual as a Black woman. 

The STM also announced Tuesday that it would be enlisting a "lawyer specializing in police ethics" to audit the transit company's preliminary findings.

"We are reading, listening and seeing what is being said and published, and we see that the relationship between us and our customers is shaken by the content of the video," STM Chairman Philippe Schnobb said in the statement.

The company previously claimed that the incident occurred after the individual didn't pay metro fare.