Protesters smashing a shopping mall at Shatin. The also attacked a restaurant filled with dining civilians.
When a group of men (later confirmed to be undercover polices) are trying to control and arrest a suspect, they were assaulted by a group of protesters to help the suspect escape.
Source:
https://hk.on.cc/hk/bkn/cnt/news/20191215/bkn-20191215150929428-1215_00822_001.html