“Protest­ing in locales such as Mong Kok … only adds to the threat of vio­lence, giv­en the pop­u­la­tion den­si­ty and the pres­ence of tri­ad soci­eties,” said Steve Vick­ers, a risk con­sul­tant and a for­mer com­man­der of the Roy­al Hong Kong Police Crim­i­nal Intel­li­gence Bureau.

Tri­ad gangs, he said, ​“may act as agi­ta­tors for either side, or sim­ply take actions to pro­tect their own interests.”