Police arrested at least 86 pro-democracy protesters Tuesday, after an attempt to clear occupied streets descended into scuffles, confrontation and chaos.

On Tuesday morning, bailiffs and contractors wearing hard hats had removed some of the barricades in the shopping area of Mong Kok following an injunction brought by a minibus company that had complained its business was hurt. Authorities have recently begun using bailiffs and the courts as a way to whittle at the protest sites.

The exercise began peacefully, with protesters offering no resistance as workers removed barricades and wooden pallets blocking the road. But as workers moved down the street, removing tents and other items — and as more protesters arrived — tensions began to rise.

As the day wore on, police made several attempts to force protesters back, using batons, shields and pepper spray — and hauling to the ground, handcuffing and arresting any who did not retreat quickly enough. Protesters wore masks and goggles, and some carried wooden shields to defend themselves. Some staged “mobile occupations,” blocking traffic on surrounding streets.

Tuesday’s action cleared a 160-foot stretch of Argyle Street in Mong Kok, one of three sites where protesters have occupied roads for the past two months during their calls for genuine democracy.

The protesters who were detained face charges including criminal contempt of court, unlawful assembly, resisting or obstructing police officers, assault on a police officer, and possession of an offensive weapon, police said.

Mong Kok, a working-class neighborhood, has been home to a more unruly crowd of protesters than the main occupation site in the Admiralty district, but demonstrators in Mong Kok have also faced more anger and threats from local residents. As the barricades were dismantled, a small crowd of onlookers applauded.

Protesters remained defiant, however, and blamed the police for the violence that erupted later.

“I feel people are more united through tonight’s violence,” said 27-year-old designer Tricia Ling. “It looks like people’s minds are back to the first week of the protest, when we stood strong.”

Support for the civil-disobedience action mounted by the pro-democracy protesters has diminished in recent weeks, opinion polls show, although support for democracy remains strong.

“Even if they clear this place, our will to fight for genuine universal suffrage hasn’t changed,” 27-year-old protester Ken Chu, wearing a bright yellow safety helmet and a gas mask, told the Reuters news agency. “It will only inspire people to think of other ways to continue this movement.”

Bailiffs said they would return Wednesday morning to clear the remaining barricades in the Mong Kok area, in compliance with another injunction brought by taxi drivers.

“Tomorrow will be the main event,” lawmaker Albert Chan of the radical pro-democracy People Power party told the Associated Press. “There will be more people joining the resistance. Maybe there will be more arrests tomorrow.”

Police said they were duty bound to preserve public order, and they warned members of the public, especially students, to stay away from Mong Kok. “They should not mix with the radicals and troublemakers and be incited or used by others to commit any illegal acts,” they said in a statement.

As the night wore on, thousands of police officers and protesters continued to throng the streets.

“I will come to Mong Kok as soon as I can after work tomorrow to help the students here,” said 30-year-old construction supply worker Hei Chung. “If there are more people watching, it will be safer for them.”