We're ending our live coverage of the protests in Hong Kong for now.

You can read all the latest updates on the protests here.

As of 2200 local time on Wednesday, 21 officers were confirmed injured in clashes with protesters.

Nine officers have been taken to hospital, the South China Morning Post reports.

Hong Kong's government confirmed to the BBC that clashes in the city on Wednesday resulted in 72 injuries, as of 10pm local time.

Those injured ranged between 15 and 66 years old, and two men were in a serious condition.

Five former Hong Kong officials have called for the Chief Executive to withdraw the Extradition Bill following the unrest.

Former secretary for welfare Stephen Sui Wai-keung and ex-undersecretary for transport and housing Yau Shing-mu were among those who put their names to the letter, according to the South China Morning Post.

An open letter signed by the group read: "We are locally born Hongkongers who love the city and our country. We urge the chief executive to withdraw the bill as soon as possible to create room for rational discussion."

Rights group Amnesty has accused Hong Kong's police of violating international law in their "excessive response" to protesters.

“The ugly scenes of police using tear gas and pepper spray against overwhelmingly peaceful protesters is a violation of international law," said Man-kei Tam, Director of Amnesty International Hong Kong, external.

"Police have a duty to maintain public order, but in doing so they may use force only when strictly necessary. Hong Kong’s police have today failed to live up to this standard."

Police Commissioner Stephen Lo Wai-chung earlier said that officers "had no choice but to use weapons" to stop protesters from charging their lines.

Hundreds of students have been involved in school strikes today. Leung Ho Wun, a 15-year-old, is one of the organisers, and she told BBC Chinese reporter Tsung-Hsieh Lee that her school was not against the strike as long as it did not affect school work.

“Many people say that students have lost interest in politics. This is not true,” she said.

She said she was worried that Hong Kong might not be able to maintain its judicial independence following the introduction of the bill because she did not trust China's judicial system.

"We won't give up, we will keep protesting until they hear us," she said.

By Vincent Ni, BBC News Chinese reporter

There has been very limited coverage of the protests on mainland China

The top story from the official Xinhua News Agency today highlights President Xi’s visit to Bishkek.

Even on Weibo, the Chinese equivalent to Twitter, search results for phrases referring to the massive protests in Hong Kong are not shown - unless they are posts toeing the Beijing line.

The editor of the Chinese state newspaper Global Times posted on Twitter to condemn the protests as something which was "not supposed to happen in Hong Kong".

But the stringent media censorship in mainland China does not mean Chinese citizens are completely ignorant of what is happening across the border.

Some curious social media users have been asking online: "What's going on in Hong Kong?"

Some mainland Chinese people were seen joining the protests in Hong Kong over the weekend, and others have shown their solidarity on Wechat, another popular social media platform.

“Although this is Hong Kongers’ fight, the love for freedom and dignity is universal,” wrote one Wechat user. “I salute to their struggle and effort. I just hope that we are not going to see a bloody crackdown.”

Reports suggest that police are preparing another push to remove protesters from the centre of the city.

After being moved from roads around the Legislative Council in the afternoon, the demonstrators moved into main roads in the central business district and Admiralty areas where they brought traffic to a standstill. The protesters also erected more barricades.

Image source, Reuters

Today's protests are about a proposed bill to allow extradition from Hong Kong to mainland China. But there's a lot of important context - some of it stretching back decades - that helps to explain what's going on.

Here's an article that explains:

• Why Hong Kong has a special status in China
• Why only 15% of Hong Kongers call themselves "Chinese"
• Why protests are part of Hong Kong's political culture

People in at least 29 cities around the world held protests on Sunday in solidarity with the Hong Kong marchers.

Something similar appeared to be happening on Wednesday - students in Meiji University in Tokyo, Japan, held a gathering opposing the extradition bill, while there were also plans to hold a rally in London.

Image source, Getty Images

Image source, Reuters

Despite the late hour there is still a tense stand-off between police and demonstrators in the central business district, witnesses say.

The BBC has been speaking to protesters on the street. One, 30-year-old Iris Tang, said: "If I don't come out this time, there might not be a next time... I don't accept the bill because Hong Kong will lose its freedoms."

Image source, Reuters

Anson Chan, former chief secretary of Hong Kong, told the BBC that she was saddened by Wednesday's violence and that she shared the concerns about the extradition bill.

"I think today is a dark and very sad day for Hong Kong," she said. "I share the population's concern because in one fell swoop the chief executive has put forward proposals that will remove the essential firewall between Hong Kong and the mainland."

Image source, Getty Images

A Bloomberg journalist shared footage of tear gas canisters being fired during rush hour.

To recap, thousands of protesters remain on the streets of Hong Kong after hours of violent clashes with police. Police have used tear gas and rubber bullets to try to disperse the protesters.

Image source, Reuters

Image source, AFP

In a video address, Hong Kong Chief Executive Carrie Lam condemned the violence, describing "heartbreaking scenes...that damage the public peace - something no civilised, law-abiding society can endure".

"It's clear these were no longer peaceful gatherings, but organised riots," she said.

The Hong Kong Tourism Board has cancelled the city's famous Dragon Boat Carnival scheduled for 14-16 June, the South China Morning Post reported. The tourism board said it cancelled the event after "careful consideration" of the situation.

About 5,000 participants - representing some 180 teams from 16 countries and regions - had been due to take part, according to the board.

The BBC's Grace Tsoi sent this report from the scene of the protests.

Image source, Reuters

The crowds were cleared from the highways in Admiralty in a matter of hours - but many were angry at what they said were heavy-handed tactics from the police.

Many protesters - after being hit by tear gas and pepper spray - took refuge inside the MTR [metro] station. Surgical masks and trash were strewn everywhere and there were puddles of water on the usually spotless floor, from protesters washing their eyes of pepper spray.

At around 6pm, dozens of police in full riot gear appeared at Admiralty Centre - an office complex near the legislature - through the underground station. Some protesters hurled insults at them. At times, police beat their shields with batons.

“I got hit by tear gas several times. I lost count,” said Daniel, a protester in his 50s, who works in the logistics industry. His eyes were red. He said he came to take a look as he was passing by.

“I think they have gone too far. They are bullying young people,” he said, referring to the police.

Raymond Lau, 36, said he came to the scene after watching news of police using tear gas and rubber bullets on protesters. He was pepper sprayed.

“I was taken by surprise that police force were so determined to clear the crowds,” Mr Lau said. “I am angry but we have to be calm. I have faith in Hong Kongers. I don’t believe they will become rioters and keep charging.”

The UK foreign secretary Jeremy Hunt has called for calm and urged the Hong Kong government to listen to concerns over the extradition bill.

In a statement, external, he said the policy of "one country, two systems" must be upheld.

Police have used tear gas in an attempt to disperse protesters from around the Legislative Council building but the protesters are still very much on the streets, as this tweet from author Louisa Lim shows.