Violent outbursts are a rare thing to read in the news coming out of Macau. Things got rough this week for one police officer, who had to fire a warning shot from his gun to scare off three men who had been assaulting him. The motivation for the assault seems almost trivial: the officer asked the men to stop smoking in a non-smoking area.

According to a GGRAsia report, the event happened on January 3, when the police officer asked the three men to vacate a non-smoking area just outside the Galaxy Macau casino resort. The officer only sustained minor injuries, but has been given a temporary desk job so he can have a breather after the fracas. Hailing from mainland China, the three assailants face as much as five years in prison for defending their illegal smoke break.

As a result, Wong Sio Chak, Macau’s Secretary for Security, said policing would be increased around the cities casinos, and pepper spray will be provided to offices as an additional defense against unruly patrons.

It’s a little surprising that of all the crimes Macau has cracked down on in the past year, it’s smoking that would result in fisticuffs. The city has also cracked down on loan shark and money exchange operations, with each set of operations being described as orderly and without any more serious criminal element. Macau’s crackdown on smoking has escalated over time as well, but with only fines served until this incident.