On Saturday, the campaigners ignored police warnings and streamed past the designated endpoint for a rally in the latest demonstration targeting the government of the semi-autonomous Chinese territory.
Protesters called for a strike on Monday as they filled the roads in a usually bustling Mong Kok market district, in reference to demonstrators’ calls for a city-wide shutdown.
Shop owners shuttered their storefronts in anticipation of a prolonged demonstration.
Chen Daoxing, commander of the territory’s People’s Liberation Army (PLA) garrison, said the protests “should not be tolerated”, according to reports in the South China Morning Post, a Hong Kong newspaper.
The action is the latest in two months of demonstrations which were sparked by a controversial extradition bill.
Although the government suspended the bill, which would have allowed extraditions to mainland China, demonstrators are demanding the bill be taken off the table completely.
Their demands have broadened to include calls for the resignation of Hong Kong’s leader Carrie Lam and for more democracy.
On Saturday, the street along the route was completely filled with protesters, while other roads were reduced to single lanes. One black-clad protester directed traffic for a line of taxis attempting to get through.
Some passing drivers honked their horns and yelled words of encouragement, eliciting cheers from the crowd.
Later, protesters removed a Chinese national flag from a pole and hurled it into Hong Kong’s iconic Victoria Harbour.
When demonstrators reached a set of flagpoles bearing the Hong Kong flag as well as the national flag of China, one protester climbed up the pole and removed the Chinese flag.
After some debate over whether they had time to paint the flag black, they decided to throw it into the water before police could intervene.
The act is reminiscent of actions last month which infuriated the Communist Party-led central government.
After one rally a few weeks earlier, some protesters went to the liaison office, which represents the mainland Chinese government, and threw black paint and eggs at the national emblem on the building.
Police also fired tear gas at demonstrators after some of them vandalised a police station.
Officers continuously fired several rounds of tear gas to push back a group who had thrown bricks at the station and spray-painted inflammatory language on its outer walls.
Police warned earlier in the day that those who continued past the pre-approved route would be breaking the law. They called on protesters to stick to designated routes and times after violent clashes marred previous rallies in the summer-long protest movement.
Saturday’s march comes after a group of civil servants - ordered to be politically neutral - joined demonstrations in their thousands on Friday.
While the pro-democracy rallies have been largely peaceful, they have occasionally devolved into skirmishes with police after some protesters refused to disperse at assigned times.
In the past two months, demonstrators have vandalised buildings and thrown bricks, while police have fired tear gas and rubber bullets.
A former British colony, Hong Kong was returned to China in 1997 under the framework of “one country, two systems”.
The city’s mini-constitution promises certain freedoms not afforded to those in the mainland, but people from Hong Kong say Beijing has chipped away at their autonomy in recent years.
Several thousand civil servants and their supporters crowded into a public park on Friday evening to show solidarity with the movement, which has broadened to include demands for direct elections and an investigation into alleged police brutality.
Hong Kong residents have accused police of negligence after 44 people were injured last month in a mob attack that appeared to target protesters.
Authorities said their resources are stretched due to the prolonged demonstrations.
Mong Kok, the site of Saturday’s protest, is one area where protesters set up a pro-democracy demonstration zone in 2014.
Near the end of the Occupy Central protests, police officers descended on the site and tore down the metal barricades, bamboo and wooden planks protesters had used to block off key streets.