Hundreds of pro-democracy demonstrators and police faced off in Hong Kong on Wednesday night after officers cleared a major protest zone and arrested high-profile student leaders.

Joshua Wong and Lester Shum were among 116 detained in Mong Kok for offences including unlawful assembly and assaulting or obstructing police on Tuesday night and Wednesday morning, as a night of clashes – during which police used pepper spray solution – was followed by the removal of barricades from the occupied area on Nathan Road.

But protesters flooded into another part of the district as night fell again, prompting fresh scuffles. Police hit out with batons and made several more arrests.

“I am here because Hong Kong needs me,” said 16-year-old student Ben Hoi, who had been protesting for 50 days, mostly in Mong Kok. “The police have been fighting us. I am so angry. I will continue to demonstrate until we get democracy.”

A breakaway section tried to launch a flash occupation of another area, Tsim Sha Tsui, but were dispersed by police.

As of late evening, 18-year-old Wong of Scholarism, who has become the face of the protests, and Lester Shum of the Hong Kong Federation of Students were still in custody.

Facebook Twitter Pinterest Officers dismantle barricades in the district. Photograph: Demotix/Corbis

Protesters are angered by the tight restrictions Beijing has imposed on nominations for the election of the next chief executive in 2017, saying it will mean they have no real choice. Beijing argues that the introduction of universal suffrage is in itself a step forward.

Shortly before his detention, Shum told the South China Morning Post (SCMP) that he planned to continue the civil disobedience campaign when clearances began and was ready to be arrested.

Activists Szeto Tze-long from Chinese University’s Student Union and Raphael Wong of the League of Social Democrats were also held.

The SCMP said the latter wrote on Facebook that he was being held at Kwai Chung police station with Shum and Joshua Wong, adding: “We have been charged with the crimes of criminal contempt of court and obstructing a public officer. Bail may not be granted tonight, and [we] will be mentioned in a magistrate court tomorrow.”

By mid-afternoon, police and workers overseen by bailiffs had cleared Nathan Road, allowing traffic to pass along it for the first time in almost two months.

Hui Chun-tak, chief superintendent of police public relations, said 22 officers had been injured over the past two days and accused radical elements in the crowds of charging police, adding that officers had used the minimum necessary force.

Joshua Wong arrested in Hong Kong. Photograph: Facebook

The heavy police presence meant protesters were unable to reclaim the demonstration areas, even as their numbers swelled in the evening. But the crowd regrouped at a nearby junction, despite police using loudhailers urging everyone to leave the “danger zone”. Another officer held up a red sign warning: “Stop charging or we use force.”

The mood veered between defiance and almost playfulness. People at times booed and harangued officers, shouting: “I want real universal suffrage.”

Others struck up jokey chants including “I am here to shop!” – apparently a dig at chief executive Leung Chun-ying, who had earlier asked people to support businesses in the area by returning there to shop after the clearance.

But after weeks of protests, many in Hong Kong say their patience with demonstrators has run out. “This democracy they talk about is just selfishness,” said Ms Choi, who runs a T-shirt stall in the Ladies’ Market, complaining that business had slumped by 90% since protests began. “Police are right to take them away. Why did they wait so long?”

Mr Yan, who owns a traditional Chinese medicine shop on Shantung Road, said that while he supported democracy, protesters also needed to think about the livelihoods of people like him. “Rent is so high and tourists have stopped coming since the troubles began,” he said.

Wong, Rafael Wong and Lester Shum, leaders of the pro-democracy movement. Photograph: Demotix/Corbis

Police cleared a small section of the main protest zone at Admiralty last week, but left most of it. The mood there was muted on Wednesday, though there were concerns that police might now seek to clear that occupation, too.

“Last night I was in Mong Kok, but tonight I am here as I worried the police might do something in Admiralty,” said Samantha Choi, a trader who has been part of the movement since its early days. “I will stay until they kick us [out].”

Winnie Kwan, an accountant, said police actions in Mong Kok were “terrible and ridiculous”. She added: “They do not even allow us to be on the pavement? How can this be legal? The only thing we can do is to stay here in Admiralty. I intend to spend Christmas here. If the government keeps ignoring us we will have to keep finding ways to get their attention.”

Police announced late night that they had arrested seven of their officers for assault occasioning actual bodily harm. Several officers were filmed last month kicking and punching demonstrator Ken Tsang, a social worker and member of the Civic party.