It’s a strange word to describe any person with, and even more so when it comes from members of a police force whose motto is to “serve with pride and care.” Yet every week that passes seems to bring with it new videos of police officers yelling “cockroaches” at not just protesters, but now also bystanders and journalists.

And the force isn’t shy about its open advocacy of such language. In a letter last month, the chair of the Junior Police Officers Association denounced protesters as “no different from cockroaches.” That followed another letter, published in July, in which Lam condemned those who desecrated a pro-China lawmaker’s parents’ graves as creatures who cannot be called human.

While a new police assistant commander issued an internal memo calling on his staff to refrain from applying the epithet to protesters—because doing so is only “playing into their hands”—frontline officers have continued using the term. Just last week, an officer yelled “Cockroaches, shut up!” at a group of protesters and reporters, while an officer was even seen yelling the word on Sunday (Sept. 8) at a group of elderly citizens trying to play the role of mediators between young protesters and the police. And during another protest late last month, riot police similarly used the term to describe photojournalists (link in Chinese) who were trying to document the arrest of a protester. An officer is reported to have said, “Journalists? Also cockroaches.”

The practice of insulting one’s opponents with dehumanizing language has a long and ugly history. Nazis described Jews as rats, and Hutus involved in the Rwanda genocide called the Tutsi minority cockroaches. Such attempts to paint a group of people as less than human can pave the way for escalating cruelty. It’s also language that China’s state-run media has used to refer to the protesters, with Xinhua at one point publishing a cartoon of the protesters as cockroaches.

Protesters, on the other hand, now widely refer to police as “dogs.”

A police spokesman recently acknowledged that some of its officers have on certain occasions called people cockroaches, saying the use of the term is “not ideal” (link in Chinese). When asked at a news conference several days later whether officers who call reporters and protesters cockroaches are fit to carry out their duties on the front lines, secretary for security John Lee said if citizens are dissatisfied with police conduct they can put in a complaint.