Seems not much people talk about "Establish Independent Comission of Inquiry to investigate Police Misconduct and Brutality", which is one of the 5 demands from the HK protesters. HK Government sends police forces to violently suppress the demonstrations. However, i don't think the Chinese students seen these scenes, cos of blocking from China's firewall/media, nor understanding what are the reasons behind these scenes, again cos of the biased reporting that selectively misrepresents Chinese perspectives.
Ref: https://www.hongkongfp.com/2019/06/29/full-open-letter-hong-...