Thousands of pro-democracy protesters paralyzed parts of Hong Kong this morning, blocking roads in the central business district and threatening to bring chaos to the morning rush-hour after police fired tear gas and pepper spray in failed attempts to disperse the crowds.

As dawn broke, crowds continued to blockade roads leading to the heart of the financial center and besiege the government’s headquarters one subway stop to the east. New protests sprung up overnight in the shopping districts of Causeway Bay and Mongkok, with hundreds sitting in the road and erecting barricades.

Crowds mushroomed yesterday in support of a student-led protest that began Sept. 26 to oppose China’s plans to control the city’s 2017 leadership election. Swelling numbers prompted leaders of protest group Occupy Central with Love and Peace to bring forward its long-planned mass sit-in of central Hong Kong from Oct. 1.

“This is a sad day for Hong Kong,” Anson Chan, the city’s former No. 2 official, said in a statement. “Pictures of our police force firing pepper spray and tear gas into the faces of unarmed protesters will shame our government in front of the whole world.”

In the biggest clashes to rock the city for decades, anti- riot police wearing gas-masks and carrying batons and guns skirmished repeatedly overnight with demonstrators who used face-masks, goggles, plastic wrap and umbrellas to protect themselves.

PLA Rumors

Hong Kong Chief Executive Leung Chun-ying urged protesters to disperse for the stability of the city, dismissing rumors that police had opened fire or that the government planned to call in the People’s Liberation Army, which the Chinese government used to crush the student-led Tiananmen Square pro- democracy protests in Beijing in 1989. The PLA has garrisons in Hong Kong but is rarely seen on the streets.

“Hong Kong’s stable development for so long has depended on everyone’s abiding by peace and respecting the law,” Leung said in a televised speech at 1 a.m. “We don’t want Hong Kong to be chaotic or for people’s daily lives to be affected.”

The protests threaten to disrupt one of the world’s most vibrant financial centers and a gateway to investment in China. Hong Kong investors prepared for a stock-market retreat and made arrangements to work outside the financial district. More than half the companies on Hong Kong’s benchmark Hang Seng Index are from the mainland, driving the city’s $3.7 trillion stock market, the fifth-largest worldwide.

Overnight Lull

Many protesters ignored calls by some organizers to pull back at about 10:30 p.m. last night, with thousands remaining at 6 a.m. today. Some moved metal barriers to create barricades across major roads into Central, while others rested before daybreak.

“I was about to go to sleep, but then saw on TV that tear gas was being used and policemen were pointing guns at students and citizens,” said Bernard Li, a Hong Kong native who lives in Shanghai, who returned to the scene soon after midnight after attending the protest with his family earlier. “This gathering is very worthwhile. I just had a feeling I needed to come back out.”

Forty-one people were injured as of 5:45 a.m. last night, the city’s hospital authority said. Police said they arrested 78 people for offenses including forcible entry into government premises, unlawful assembly, disorderly conduct, and obstructing police officers.

A handful of policemen trying to drive a vehicle out of the protest site in Admiralty at 6 a.m. today were stopped by demonstrators and forced to leave it behind after gathering their belongings. The crowd applauded the policemen when they departed.

Resignation Demand

“Heavy-handed approaches to the students will surely backfire,” said Michael Davis, a law professor at the University of Hong Kong. “Hong Kong people have proven time and time again that if the government handles public concerns badly, the public will mobilize against them.”

Police officers have tried to minimize injuries during operations and shown self-restraint, the Hong Kong Police Force said a statement. It urged protesters to stop clashing with police.

Student federations and activist group Occupy Central With Love and Peace said yesterday that the best way to diffuse the protests would be for Leung to resign. They say that China is reneging on its promise to maintain the city’s autonomy under its “one country, two systems” agreed when British colonial rule ended 17 years ago.

Leung, who has ignored student demands for a meeting, earlier told a press briefing he was resolutely opposed to the protesters, while urging everyone to get behind political reforms so that Hong Kong’s next leader will be elected by universal suffrage.

Acrid Smoke

Protests were spurred by the Chinese government’s decision last month that candidates for the 2017 election of chief executive, the city’s leader, be vetted by a committee. The pro- democracy forces say the system is designed to produce a new leader effectively handpicked by the government in Beijing.

Tensions escalated after police began lobbing tear gas into the crowds just before 6 p.m. yesterday and clashes continued into the night.

As the crowds began to swell yesterday and push against barricades, police held up warning signs saying “Disperse or We Fire.” The police first threw tear-gas cannisters at crowds in the Admiralty district, outside Leung’s office.

Support Network

In a scene that was frequently repeated over the next eight hours, protesters briefly scattered as acrid smoke filled the air before regrouping. Demonstrators also spread to both the east and the west of the initial protest after the Admiralty subway station was closed.

Hundreds formed human chains to ferry water, umbrellas and other supplies brought by supporters to sustain protesters on the front-line.

Hugo Tam, 24 and wearing a blue England soccer jersey, was carrying a box of masks he said his mother bought.

“She told me to come here and support the people,” he said. “They have been here so long their supplies must be running low.”

Eason Chung, secretary general of the Hong Kong Federation of Students that led the initial rally, said last night that people could “preserve their strength and retreat,” while he welcomed anyone wanting to continue the action.

The clashes were the city’s biggest since unrest in the 1960s led by pro-Communist groups inspired by Mao Zedong’s Cultural Revolution.

The violence capped protests initiated by student groups on Sept. 26 that gained momentum over the weekend.

Leaders Freed

Three student leaders who were arrested at the start of the protests were released from jail yesterday, according to Michael Vidler, the lawyer for 17-year-old Joshua Wong of a group called Scholarism.

Wong, who escalated protests late on Sept. 26 when he urged demonstrators to climb the gates of the government headquarters, was ordered released by a judge who ruled his detention was unlawful, Vidler said.

The protests may disrupt the start of Golden Week, a week- long holiday in China when hundreds of thousands of people from the mainland travel to Hong Kong. They provide an annual boost to sales of luxury brands such as Prada, Louis Vuitton and Patek Philippe. More than 54 million people visited the city last year, almost eight times the population, with mainland tourists accounting for about 75 percent of the total.

No Compromise

Leung signaled yesterday that the protests would not lead the Chinese government to compromise on its plans for the vote.

The National People’s Congress Standing Committee of the Communist Party’s decision on the election procedure was made “after detailed and careful deliberation of the actual situation of Hong Kong and the views of various sectors of the community. It is legally binding.”

The Transport Department advised motorists not to drive to Hong Kong island today and closed more than a dozen roads, disrupting bus services. Schools will be closed in two districts on the island because of traffic congestion, the government said.

Hong Kong’s Professional Teachers’ Union yesterday called on members to strike today, condemning the “government and police’s insane behavior” against the protesters. A student boycott of classes that started Sept. 22 will be extended indefinitely, the Federation of Students said.

“We can take further action, so we call on Hong Kong students to boycott classes, workers to boycott work, and business people to boycott the market,” lawmaker Lee Cheuk-yan said earlier today.