In a separate channel made up of secondary school students – mostly strangers to one another – questions flowed back and forth about the logistics of organising a strike.

“Does anyone in Tseung Kwan O have ribbons? I would like to dish them out at school tomorrow,” a member wrote.

At a busy junction in Causeway Bay, a young man handed out self-made, black-and-white A4-size leaflets to office workers and mainland tourists, urging them to go on strike when the debate on the unpopular bill resumed in the legislature on Wednesday.

Death threats for Carrie Lam as more protests loom over fugitive bill

Such frenetic activity – in leaderless groups operating on encrypted platforms – appeared to be the norm across broad swathes of Hong Kong on Tuesday as ordinary people began mobilising to take action during the debate.

Many were making plans to gather at Tamar Park in the morning for a rally billed as a “picnic”.

The controversial bill they are opposing will allow the transfer of suspects to jurisdictions with which the city does not have an extradition deal, including mainland China. Critics fear it will leave Hongkongers at risk as fair trials are not guaranteed.

On Tuesday, the Tai Kwun centre for heritage and arts in Central district announced its JC Contemporary gallery would operate with limited capacity on Wednesday and that no tickets would be available for sale at the door for its exhibition of work by leading Japanese artist Takashi Murakami.

Protesters brace for fresh showdown with Hong Kong police over bill

According to the Hong Kong Artist Union, exhibition guides at the JC Contemporary gallery wrote to Tobias Berger, head of arts at the historic compound, and asked that the gallery be closed on Wednesday. Guides are expected to join strike action.

Pupils of at least 72 secondary schools have initiated a petition calling on fellow pupils to join the class boycott on Wednesday, with student leaders of seven universities making a similar appeal.

“The government and the chief executive have ignored the opinions of 1.03 million people,” Gigi Chow Mei-chi, the external secretary for Polytechnic University’s student union, said, referring to the turnout of the Sunday march as estimated by the organisers.

“We at the student union absolutely cannot accept this … We need to tell the government no Hongkonger accepts this evil law,” she said.

Protests loom for teachers, social workers as Catholic Church urges calm

Fung Wai-wah, president of the Hong Kong Professional Teachers’ Union, said they would discuss with members the possibility of a strike, including the date, duration and how to ensure student safety.

“We prefer suspending normal classes, but secondary and primary school students can stay in schools and have alternative arrangements, such as taking civic education lessons,” Fung said. “But the clear message we got from teachers is the government must withdraw or at least shelve the bill.”

Several accountancy firms and banks, including Deloitte, Ernst and Young, HSBC, Hang Seng Bank and Standard Chartered, whose offices are located near the legislature, are also allowing their staff to work from home or adopt flexible working arrangements on Wednesday, while the Eaton Hotel in Jordan is allowing its employees to attend the rally.

Veteran unionist and activist Lee Cheuk-yan said the campaign was an important chapter in the city’s civil disobedience movement as it had evolved so much from a top-down manner – where supporters wait for the organisers’ instructions – to a spontaneous, bottom-up approach.

“All the organisers need to do is to provide a general direction, say the date of the protest, and the citizens would come up with their own ways of mobilising people,” he said. “It is an empowerment process and the snowballing effect is way more powerful.”

“Next week will be the real D-Day and we hope society can keep up the strike,” Lee said.

Supporters of the bill remained largely silent on Tuesday but four Chinese business bodies – the Chinese Enterprises Association (CEA), Chinese Banking Association, Chinese Securities Association and Chinese Asset Management Association – held a rare press conference to condemn “violent acts” during Sunday’s late night eruption of clashes and voiced support for Hong Kong leader Carrie Lam Cheng Yuet-ngor’s bill.

Extradition row ‘a real challenge’ but no crisis, says Hong Kong’s No 2

They said the legislation was needed to uphold the spirit of the law, maintain the core values of Hong Kong, and prevent the city from becoming a safe haven for criminals.

CEA vice-chairman Yan Feng, a delegate of top advisory body the Chinese People’s Political Consultative Conference, said some people had exaggerated the bill’s impact in a bid to arouse fear.

“We issue a strong condemnation to violent acts committed by troublemakers,” Yan said, without taking any questions. He also called on Legco to scrutinise the bill peacefully and rationally.

While employers were silent on how they would view their employees’ actions on a working day, the Social Welfare Department and Education Bureau counselled caution.

The department urged all social welfare practitioners to “display professionalism while expressing their views and to ensure that any action will not affect services or users’ interests”.

Choi urged schools and teachers planning to carry out a strike to put students’ safety and interests first and not disrupt normal operations, adding the bureau would closely follow the boycott and remain in close contact with schools to provide help if needed.

Additional reporting by Sum Lok-kei, Enid Tsui and Victor Ting