NSW Police have publicly defended one of their officers after a six-second video, filmed by commuters at Cabramatta train station in south-west Sydney on Monday night, appeared to show the officer repeatedly punching a man who was pinned face down on a platform. The footage, which circulated widely, prompted concern about the use of force, but police say it captured only "an isolated moment" of a wider incident and that the officer used an "approved manoeuvre".

According to police, officers had been called out over reports of a 21-year-old man allegedly armed with a knife and behaving aggressively towards female commuters at nearby Canley Vale. The man is said to have assaulted a male commuter who tried to intervene before boarding a train to Cabramatta, where he allegedly threatened others and then tried to flee, being arrested after a short foot chase. Police allege he later spat at and assaulted several officers after being taken to hospital, and he has since been charged with 10 offences. A commander has reviewed the arresting officers' body-worn camera footage.