Rampage culminated in a large-scale eruption of violence across Hong Kong on Friday night, which forced a plain-clothes police officer to fire a shot in self-defense and all train services to be suspended after the Hong Kong Special Administrative Region (HKSAR) government enacted an anti-mask law.

Rioters burn items at the Causeway Bay metro station entrance in Hong Kong on October 4, 2019. (Photo: AFP)

Rioters committed riotous acts in various districts in Hong Kong by setting fire, vandalizing MTR stations, breaking glass panels of shops, throwing bricks and petrol bombs, and beating up MTR staff and bystanders, taking the law into their own hands, the Hong Kong police said in a statement Friday night. 

Around 9pm on Friday night, a large group of rioters attacked a plain-clothes police officer in Yuen Long district. The police officer fell onto the ground and was beaten up by the group. 

Facing serious threat to his life, he fired one shot in self-defense, the Hong Kong police said in a separate statement.  

A rioter then threw a Molotov cocktail at him and his body caught fire. While evading the blaze, he dropped his pistol and magazine on the ground. A rioter tried to take the pistol and was stopped by the police officer. 

While waiting for reinforcement, another Molotov cocktail was thrown at the officer and his feet were on fire. The officer therefore was unable to pick up the dropped magazine when he retreated.

The police appealed to the public to return any bullets or bullet casings if found as it is an offence for any person to possess ammunition without a license. 

Assaulting police, damaging shops, and MTR train stations, vandalized mainland banks' ATM machines, rioters went on the rampage across the city, pushing a large part of Hong Kong into paralysis on Friday night.  

The Global Times reporters saw black-clad rioters commit  arson on Causeway Bay MTR station during the night, breaking several shops and vandalizing branches of the Bank of China and China Construction Bank by spray-painting insulting graffiti and breaking windows. 

Fire alarms were heard on the streets, and the shopping district was left with damaged shops, dismantled road railing, scattered stones, and barricades. 

MTR halted all train services out of safety concerns on Friday night following damage and arson committed by rioters at a number of stations, and allegedly some trains in operation, causing panic among travelers. 

A group of rioters attacked a direct train linking Guangzhou, South China's Guangdong to Kowloon on Friday night, smashing the windows of one carriage despite that there were still passengers on the train, as an online video showed. 

"Those rioters are just inhumane, some passengers from that carriage were so scared that they ran into our carriage to avoid this disaster," a passenger onboard surnamed Chen later told the Global Times on Friday. 

From Kowloon to Hong Kong Island to the New Territories, rioters posed a serious threat to people's safety and public order, and the police urged residents to stay in safe places. 

The HKSAR government enacted the anti-mask law by invoking emergency powers on Friday afternoon and sparked fresh opposition from the anti-government groups. From Saturday, protesters taking part in illegal assemblies are not allowed to wear masks, which is expected to deter rioters from taking part in illegal activities. 

Ordinary Hong Kong people said they feel heartbroken to see their city being destroyed little by little by those rioters. Some also began to stock food and daily necessities in case of emergency or disrupted public transport.