"They want to arrest key people on the front-line to sap the resistance of the movement, but they will fail," said Vincent Man, a 26-year-old activist in a blue T-shirt and bandana.
"We will keep fighting and win new streets to expand the occupation zone," he added. "Tomorrow will be another big battle," he said, referring to a second court order to clear away a major protest encampment on a major road in Mong Kok.
"We won't allow them to do that. Many people will come out."
Police are taking no chances, and have readied three to four thousand officers for the task, according to media reports.
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Workers had earlier moved wooden blockades from the road after demonstrators dismantled tents and packed up their belongings. The injunction was granted to a bus company that said the blockade had hurt business.
Signs of splintering
Some protesters heckled and held up yellow banners demanding Beijing allow full democracy in the global financial hub.
"Even if they clear this place, our will to fight for genuine universal suffrage hasn't changed ... it will only inspire people to think of other ways to continue this movement," said protester Ken Chu, clad in a bright yellow safety helmet and a gas mask.
Hong Kong leader Leung Chun-ying, who has called the protests illegal, urged activists to go home.
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The restiveness in Mong Kok contrasts with a largely peaceful partial clearance of the largest protest site next to government buildings in Admiralty last week.
The pro-democracy movement is showing signs of splintering, with radical voices calling for escalated action after nearly two months of stalemate in which Hong Kong and Chinese leaders have refused the protesters' demands for a free election with open nominations for Hong Kong's next leader in 2017.
Mong Kok has been a flashpoint for street brawls between students and mobs intent on breaking up the prolonged protests that have posed a thorny political challenge for China's Communist Party leaders.
In August, Beijing offered Hong Kong people the chance to vote for their own leader in 2017, but said only two to three candidates could run after getting majority backing from a 1200-person "nominating committee" stacked with Beijing loyalists.
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More than 100,000 people took to the streets at the peak of the protests but numbers have dropped to a few hundred scattered in tents over three main sites amid dwindling public support.