Police used pepper spray and batons to fend off hundreds of pro-democracy protesters gathered in Hong Kong’s densely populated Mong Kok district on Friday night as they attempted to reoccupy a busy intersection cleared earlier in the day.

Several protesters were seen knocked to the ground or carried away by police; at least one journalist was reportedly pepper sprayed, and another was detained.

“I was retreating, and one of the officers beat me with his club,” said protester Anthony Lo, 25, pointing to the side of his head. “We’re trying to occupy the road, and they’ve been using pepper spray.” Lo said he had come to Mong Kok, a smaller protest site than the main occupied area in the financial district, because he heard that police were trying to clear the roads. “If they get rid of the defence line, I’ll leave,” he said. “But now, I’m here to help.”

Chaotic scenes began to unfold about 15 hours after police moved in to clear tents, canopies and barricades at Mong Kok. While the area was sedate for much of the day, it began to fill up after schools closed and the work day ended.

During the standoff, large crowds of young protesters intermittently broke past police cordons and sat cross-legged in the middle of a busy side street, ignoring orders to disperse. They chanted slogans and sang songs. A few hundred yards away, on Nathan Road, the main thoroughfare, a dense crowd of protesters, many holding umbrellas to defend against teargas, clashed directly with baton-wielding officers.

One protester was seen bleeding from his forehead as he was carried to a police van, moments after he was forced to the ground by officers.

Police attempted to clear protesters from one side street by driving fire trucks and ambulances directly up to the crowds, their lights flashing. Protesters then stepped aside and regrouped once the vehicles had passed.

The police force appeared at times to be spread thin; when protesters began to crowd around police cordons, officers retreated and reappeared moments later with reinforcements. “He hit me!” one protester shouted, pointing his finger at a policeman. “Show me your badge number – I’m going to report you!” The officer walked away and was replaced immediately by another.

One block south of the clashes on Nathan Road, hundreds of protesters milled about and sat chatting in the middle of the road, untouched.

The police operation began at dawn on Friday – the third attempt in recent days to retake streets from protesters – after Leung Chun-ying, Hong Kong’s chief executive, sought to defuse a standoff with student-led democracy protesters on Thursday by reviving an offer of talks over democratic reforms in the city. However, Leung warned that police wouldn’t refrain from clearing protest sites during talks.

The protests have disrupted traffic in key roads and streets in three business districts since 26 September. Protesters are pressing for a greater say in choosing the semi-autonomous Chinese city’s leader in an inaugural direct election, promised for 2017. Students and activists oppose Beijing’s ruling that a committee stacked with pro-Beijing elites should screen candidates in the election. That effectively means that Beijing can vet candidates before they go to a public vote.