Opponents of the Occupy Central movement harassed and attacked protesters on October 3, a week into the massive pro-democracy sit-in occupying the city's center demanding free and fair elections in Hong Kong.
The pro-Beijing thugs, as some described them, accused the protesters of affecting their daily work and began tearing down protest banners and booths. When the protesters attempted to stop them, they were attacked themselves. Some of the people behind the violence were wearing blue ribbons, a sign of support debuted at a recent pro-government protest for police and their use of tear gas .
The confrontation in Mongkok resulted in a number of pro-democracy protesters injured. Ling Nan narrated how the men  looking for trouble moved into the area of the sit-in on citizen media site inmediahk.net:
About 3 p.m., around 100 middle-aged men roamed around in Nathan Road and slowly surrounded the sit-in protesters in various spots. Then they shouted: “Police, just close one eye and let us beat them up!” The middle-aged men tore away the banner and cursed the volunteer duty team who was guarding the resources under the booths. They said they were against Occupy and marched towards the sit-in area at the crossing of Nathan Road and Argyle Street. On their way, they attacked the protesters at the sit-in.
[…] A passerby tried to stop an anti-Occupy Central man from hurting two young people. The thug pointed at him in the face with a blade, saying, “You have the guts? Come with me to Tiananmen, mother f**ker!” The passerby tried to walk away, but the guy chased after him, yelling, “You have the guts? Come with me to Tiananmen, mother f**ker!” and another anti-Occupy Central mob surrounded him.
A social worker, Ms Lam, who is a volunteer duty team member in Mongkok, accused the police  of turning a blind eye to the attack:
Since 6 or 7 p.m., more and more anti-Occupy Central thugs arrived. The sit-in protesters felt threatened. Ms Lam said they looked fierce and kept cursing the protesters, throwing water bottles at them. […] The situation was out of control. There were very few police officers and the volunteers had to lend their loud speaker to the police to deal with the situation. About 10 protesters decided to leave and the police led the way. But later a police officer came to the sit-in site and warned the protesters that the assembly had put others in danger, and if they did not leave they would be arrested. The remaining protesters were very angry. They were the victims of a violent attack and the police now accused them of being dangerous. They did not even give a warning to the anti-Occupy Central thugs who had stirred up the conflict. The protesters then refused to leave because of the injustice of the police. They decided to stay behind.
Because the police were not taking action, thousands of pro-democracy protesters rushed to Mongkok to confront the attackers. Some discovered that police officers had secretly released one of the men who instigated the violence and safeguarded him into a taxi. Outraged, they surrounded the Mongkok police station demanding arrests.
A similar situation happened in Causeway Bay, but on a smaller scale. Chu Hoidick described  the scene for inmediahk.net:
Around 6 p.m., a group of thugs with face masks walked into Yee Wo Street and Jardin Street outside SOGO [a landmark department store]. They attacked the sit-in protesters and tore down the blockade.
We anticipated that what happened in Mongkok would repeat in Causeway Bay, so we had built another blockade near the stage to safeguard the protesters if the thugs surrounded us.
More and more citizens came to protect us after 7 p.m. and the thugs began to retreat. A group of police officers exited the subway and we found ourselves confronting police rather than thugs.
Our position was clear: We would continue to stay and fight against police officers’ attempts to disperse us. A student and I took turns and urged citizens to stay at the sit-in site with loudspeaker.
By 8 p.m., only a few thugs with blue ribbon [which supports police] had stayed behind cursing the protesters. The situation had calmed down. We heard that sit-in protesters in Mongkok had reclaimed their site. We regained our spirit and would carry on with our sit-in.
Female protesters were targets of the physical and verbal harassment, but police ignored their complaints and refused to take action. A group of 30 NGOs for women has issued  a joint statement condemning the sexual violence:
We have already received numerous calls for help from citizens who have been targets of verbal sexual harassment, including, “if you come out to demonstrate, you should expect to begroped!” and “you have big boobs so why not let us fondle them!” and so on.There were also many women who were directly indecently assaulted, and there were also rumors that the anti-occupy movement thugs have organized themselves into a “groping troop”. This type of sexual assault and indecent assault obviously stem from gender inequality, which treats women as inferior. We are outraged by such shameless behavior! Collectively, we:
1. Strongly condemn the use of sexual violence against women by the anti-occupy movement thugs.
2. Urge those assaulted not to remain silent, and need not be beaten down by sexual violence. All protesters should stand up and defend the bodily rights and autonomy of everywoman.
3. Urge that the police must immediately investigate and maintain law and order, they must prevent the anti-occupy movement camp from committing crimes in an organized manner; they must arrest suspects on the spot.
In the evening, the city's Chief Executive Leung Chun-ying released a video urging  protesters to leave the sit-in and cooperate with police, but he failed to condemn the violence of the thugs.
A day before, the Hong Kong Federation of Students, one of the key organizations behind the pro-democracy movement, had accepted the offer of talks with the government's Chief Secretary Carrie Lam. Given the many eyewitnesses, including those injured, reporting that police did nothing to stop the attackers but instead threatened to arrest the sit-in participants, the federation has canceled the dialogue.