Scuffles broke out between police and protesters Tuesday afternoon, as an operation to clear a protest site at Mong Kok turned chaotic.
Riot police appeared on the scene shortly after 3pm.
Before that, officers are seen pinning down protesters and tying their wrists with cables, before marching them off to police vans.
Some 15 minutes before, the officers had issued a “final warning” to protesters to vacate the site. Otherwise, they say, arrests will be made and “minimum force” will be taken.
The latest development comes five hours after bailiffs, enforcing a court injunction for Argyle Street to be cleared, began dismantling barricades with the help of construction workers in hard hats.
Protesters initially put up little resistance, and the authorities made slow but sure progress over 10m of the four-lane road.
But in the afternoon, a stand-off resulted when protesters refused to leave the site, saying that the court injunction empowers the bailiffs to clear barricades but not people.
The bailiffs began dismantling barricades slightly before 11am on Tuesday.
With the help of the construction workers, they snipped the plastic cords holding wooden barriers together at a traffic junction at Argyle Street.
As the bailiffs, acting on a court injunction, moved in to remove the barriers, protesters jeered loudly with some shouting "I want genuine universal suffrage" and showing the three-finger salute made famous by the Hunger Games movies.
Local residents heckled them, calling them "running dogs" and to "pack up".
As the bailiffs moved forward, the crowd of protesters - mainly elderly - became more agitated, shouting, "The CCP is here!", and hurling Cantonese vulgarities at them.
Some distributed face masks. One said: "We will not fight them. But if the police use force against us, we will resist them with our bare fists and bodies."
Watchful police officers are on standby.
The removal operation proceeded slowly after bailiffs read out the court order that authorised them to clear the section.
Together with construction workers, bailiffs began to cut the cable cords that bind the barricades with no resistance put up by protesters.
But it is unlikely to clear the neighbourhood entirely. Protesters have said that they intend to simply move to another section of Mong Kok.
Local resident Choi Ming, 63, a retired public servant, had rounded up his friends to witness the operation. "We supported them initially because it was about democracy. But it's gone on for far too long."
The Occupy movement is in its 58th day.
The protesters, who have been occupying a long stretch of Nathan Road in Mong Kok, have been formally notified that a clearance operation may take place on Tuesday afternoon, Radio Television Hong Kong reported on Monday.
The High Court had granted a taxi drivers' group an injunction earlier in November to remove barricades put up by the protesters in the Mong Kok site as well as the main protest site in Admiralty on Hong Kong Island.
The pro-democracy movement, which drew more than 100,000 at its peak in late September to early October, has attracted rising public resentment over the traffic gridlock and other inconveniences, as well as protester fatigue.
A poll by the Chinese University of Hong Kong earlier in November found that over two-thirds of those surveyed said the protesters should end their occupation immediately.
The protesters are demanding open nominations in the city's Chief Executive election in 2017.
Beijing has said it will allow a vote in 2017, but only for candidates screened by a committee.
With input from AFP, Reuters