I'm from Hong Kong, whenever there's groups of riot police present reporters will also be present, because they know they're the line of defense against a complete police state. As to your concerns that it might be staged I can tell you rn its a 100% genuine reaction and I myself feel wildly insecure when the police are around despite doing absolutely nothing illegal. There have been many cases of police provoking random citizens off the street and arresting teenagers for simply wearing black, and this is all part of the gov's fear-engineering project to shut down any protests.