Thousands of others were unable to go to work, with transport links shut down, while others gave their staff the day off to join the call for a general strike designed to get the government's attention by targeting the city's economy and status as Asia's financial hub. Hundreds of flights were also cancelled as airport and airline staff joined the strike.

"Such extensive disruptions in the name of certain demands have seriously undermined Hong Kong’s law and order and are pushing our city, the city we all love and many of us helped to build, to the verge of a very dangerous situation," Ms Lam told media at a press conference.

"As a result of these widespread disruptions and violence, the great majority of Hong Kong people are now in a state of great anxiety."

Hong Kong's Hang Seng Index was down 3 per cent in morning trade.

It was the fourth consecutive day of mass protests and disruptions in Hong Kong. Police fired tear gas at masked protesters on busy city streets on Saturday and Sunday after activists barricaded roads, lit fires, surrounded police stations and briefly blocked cross-harbour tunnels.

Protesters burn cardboard to form a barrier in a stand-off with police in Hong Kong. AP

Pro-democracy activists labelled Monday "5th August. It's now or never", saying they hoped as many as 500,000 people would go on strike to send a clear message to the Hong Kong government.

"Summer of discontent will continue. Calls for democracy will never end under the crackdown on human rights," pro-democracy activist Joshua Wong said in a tweet..


Ms Lam said the unrest had gone beyond a controversial extradition bill which the government announced would be suspended in June. However, her first appearance before the press in weeks failed to appease the protest movement. Demonstrators have called for her resignation, the complete withdrawal of the extradition bill, an independent inquiry into the way police dealt with protesters and the withdrawal of rioting charges which carry prison sentences of up to 10 years.

"It is a time for me to continue to lead my team to address those problems and try and bring Hong Kong out of the current difficult situation. I don't think at this point in time, the resignation of myself or some of my colleagues will bring about a better solution," she said.

Ms Lam blamed the unrest on a small group of demonstrators who were using the extradition bill to conceal "ulterior motives" which would destroy Hong Kong. She was flanked by her senior economic advisers, who warned of the damage the unrest was doing to business, particularly in hospitality and retail. However, her top security advisers were not present.

The only new announcement on how the government would deal with unrest which shows no sign of ending was that it would hold daily press conferences with police and government officials.

"This is a time for us to rally together and set aside differences and bring back order and say 'no' to chaos," she said.

The protests in Hong Kong started two months ago, triggered by concern about a bill that would have allowed criminals and suspects to be sent to China that has morphed into a response to wider concerns about the erosion of civil liberties under Chinese rule.

Authorised and peaceful marches to protest the bill in June attracted more than 2 million people, according to organisers. Unauthorised protests taking place almost every weekend have become increasingly violent, with police firing tear gas and rubber bullets at protesters they say have been using petrol bombs and hurling bricks or metal rods at officers.

China has condemned the unrest, which many see as a direct challenge to its authority, but has refrained from sending in People's Liberation Army (PLA) troops.