By Clare Jim and Jessie Pang

HONG KONG (Reuters) – Hong Kong braced for strikes, transport go-slows and another mass demonstration in protest against a proposed extradition law that would allow people to be sent to China for trial, as the Chinese-ruled city’s leader vowed defiance.

Hong Kong Chief Executive Carrie Lam said she would push ahead with the bill despite deep concerns across vast swaths of the Asian financial hub that triggered its biggest political demonstration since its handover from British to Chinese rule in 1997.

In a rare move, prominent business leaders warned that pushing through the extradition law could undermine investor confidence in Hong Kong and erode its competitive advantages.

The extradition bill, which has generated unusually broad opposition at home and abroad, is due for a second round of debate on Wednesday in the city’s 70-seat Legislative Council. The legislature is controlled by a pro-Beijing majority.

An online petition has called for 50,000 people to surround the legislature building at 10 p.m. (1400 GMT) on Tuesday and remain until Wednesday.

Britain handed Hong Kong back to China under a “one-country, two-systems” formula, with guarantees that its autonomy and freedoms, including an independent justice system, would be protected.

But many accuse China of extensive meddling, denying democratic reforms, interfering with local elections and the disappearance of five Hong Kong-based booksellers, starting in 2015, who specialized in works critical of Chinese leaders.

Sunday’s protests plunged Hong Kong into political crisis, just as months of pro-democracy “Occupy” demonstrations did in 2014, heaping pressure on Lam’s administration and her official backers in Beijing.

She warned against any “radical actions”, following clashes in the early hours of Monday between some protesters and police after Sunday’s otherwise peaceful march.

Police erected metal barriers to secure the council building as a small number of protesters started to gather on Tuesday evening despite torrential rain and thunderstorm warnings. Police conducted random ID checks at train stations.

Pro-democracy lawmaker Claudia Mo urged people to join the rally and encouraged businesses to strike “for a day, or two, or probably for one whole week”.

Nearly 2,000 mostly small retail shops, including restaurants, grocery, book and coffee shops, have announced plans to strike, according to an online survey, a rare move in the staunchly capitalist economy.

Eaton HK Hotel, which is owned by Langham Hospitality Investments and operated by Great Eagle Holdings, said it respected workers’ “political stances” and would allow them to rally.

The student union of several higher education institutions and the Hong Kong Professional Teachers’ Union urged people to strike on Wednesday. Nearly 4,000 teachers said they would rally.

Human rights groups have repeatedly cited the alleged use of torture, arbitrary detentions, forced confessions and problems accessing lawyers in China, where the courts are controlled by the Communist Party, as reasons why the Hong Kong bill should not proceed.

“When the fugitive extradition bill is passed, Hong Kong will become a ‘useless Hong Kong'” said Jimmy Sham, convenor of Civil Human Rights Front. “We will be deep in a place where foreign investors are afraid to invest and tourists are afraid to go. Once the ‘Pearl of the Orient’ (it) will become nothing.”

The Catholic Diocese of Hong Kong called on the government not to pass the bill “hurriedly” and urged all Christians to pray for the former colony.

A staff union affiliated to a pro-democracy labor group under the New World First Bus Company called on its members to drive at the speed of 20-25 kmh (12-15 mph) to show their opposition to the proposed law.

A Facebook post called on people to enjoy a picnic next to government offices on Wednesday, describing the area as “among the best picnic sites”. The post has attracted close to 10,000 responses from people promising to attend.

Beijing-based consultancy Gavecal said some bankers in Hong Kong were reporting that many mainland clients were shifting their accounts to Singapore, fearing they could come under scrutiny in the financial hub.

“MISSTEPS COULD BE COSTLY”

Many residents of the financial center, both expatriate and local, are increasingly unnerved by Beijing’s tightening grip over the city.

China’s foreign ministry said on Tuesday that Hong Kong matters are purely a Chinese internal affair and China demands the United States stops interfering in Hong Kong’s affairs.

The comments came after Washington said on Monday it was gravely concerned about the proposed law and warned that such a move could jeopardize the special status Washington affords Hong Kong.

Prominent business figures urged the government to tread cautiously to protect Hong Kong’s competitiveness.

“The integrity and independence of (Hong Kong’s) legal system are absolutely central to Hong Kong’s future,” said Fred Hu, founder and chairman of China-based private equity firm, Primavera Capital Group.

Activist investor David Webb, in a post on Lam’s Facebook page, urged her to send the bill to the Law Reform Commission for further study.

“If you press ahead and bulldoze the bill through LegCo, then you will probably get the legislation passed, but at huge political cost and damage to the international credibility of HK for due process when reforming its legislation,” Webb said.

(Additional reporting by Kane Wu, James Pomfret, Greg Torode, Anne Marie Roantree, Felix Tam and Vimvam Tong; Writing by Anne Marie Roantree; Editing by Paul Tait and Nick Macfie)