On a holiday meant to celebrate the birth of China’s communist republic, Hong Kong residents instead swarmed the streets Wednesday to protest Beijing’s iron grip over their government and demand democratic reforms.

The massive crowds appeared to be one of the biggest amid a week of demonstrations that have brought large parts of the city to a standstill.

Throughout Hong Kong, it was a day of jarring images and symbolism as authorities tried to carry on with National Day celebrations only to have protesters respond with acts of emotional though peaceful defiance.

Hong Kong’s top official, Leung Chun-ying, began the morning sharing a champagne toast with other Chinese officials while demonstrators nearby booed and jeered. Then, as China’s national anthem played, a group of student protesters turned their backs on a Chinese flag being raised and silently crossed their arms above their heads in a gesture of objection to the Chinese government.

A ceremony planned later to honor Hong Kong war heroes was canceled. And an afternoon event at Victoria Park drew sparse attendance, even as massive crowds began converging near government headquarters, the heart of demonstrations in recent days.

Hong Kong’s political fault line with Beijing

Protest leaders also warned that pressures could intensify if authorities ignore their demands, which include Leung’s resignation and forcing Beijing to back down on plans to vet candidates in Hong Kong elections. The next step, protesters said, could be attempts to occupy key government buildings.

Such as move would be a major test for authorities, who have generally held back security forces since clashes on Sunday. Already, there are hints that Beijing’s patience is running out.

An editorial read on China’s state broadcaster CCTV said Hong Kong residents should not interfere with efforts to “deploy police enforcement decisively” and “restore the social order in Hong Kong as soon as possible,” according to the Associated Press.

The message also aimed at a wider audience — putting the entire nation on notice that protests inspired by Hong Kong would be tolerated. It may have caused some to think twice. In Macau — a former colony like Hong Kong with some degree of autonomy — just a few hundred protesters gathered late Wednesday for a demonstration of their own.

For many who have remained ambivalent about the Hong Kong demonstrations, the day was in many ways the culmination of months — and even years — of debate about their government, Chinese rule and the future of Hong Kong, a former British colony turned over to China in 1997. It all boiled down to this simple choice: to join in protest or not.

It was a decision that weighed heavily on some.

One medical student on the streets said he had spent every night since the protests began Sunday arguing with his father, who called the student-led protests not just illegal but pointless.

“He told me, ‘This changes nothing.’ He said, ‘These people occupying the streets are breaking the law.’ And I agree with him,” the student said of his decision to finally join the protests. “But I also feel more proud to be from Hong Kong than I’ve ever felt before.”

The student, who asked to be identified only as Lau for fear of embarrassing his father, said: “Maybe nothing will change after all this, but at least we can say we stood up for ourselves.”

Another student, Timothy Huk, 23, said his parents also urged him to stay away.

“There is a generational difference for many families in how we think about this,” he said. “They lived through the era of June 4 [the Tiananmen Square crackdown]. We did not. They worry about what happens if we do this. We worry about what happens if we don’t.”

Other parents not only supported the protests but brought their school-age children with them.

“I wanted my son to see for himself, this is what democracy looks like,” said Carman Mok, 46, his sixth-grade son in tow.

With Wednesday beginning a two-day holiday, many Hong Kong residents were freed by their jobs and family schedules to join the demonstrations. But others throughout the city remain opposed to the protests, including some who agree with its aims.

All week long, Shan Cheung, 37, said she has watched the demonstrations unfold from her job in a nearby building. “It’s made me so sad. The goal is good, but this is not the way to achieve it,” she said.

“The protesters keep demanding that [Hong Kong Chief Executive] C.Y. Leung step down. Who is China going to send to replace him? Just another puppet of Beijing,” she said.

“The reality is that Hong Kong belongs to China,” she went on. “If you want to change the system, do it from the inside. Get into government. Do it step by step. Don’t try to do it by sleeping in the streets and singing songs.”

As the demonstrations drag on, Shan said she fears all sides are facing a lose-lose scenario. Hong Kong’s government is losing credibility. Beijing is facing increasing pressure to crack down on the demonstrations. And in the end, she believes, protesters will not get the reform they want.

With a foot in both camps of Hong Kong’s political divide, former chief secretary Anson Chan is part of Hong Kong’s older generation, but he has joined activists in lobbying for electoral reform.

For months, she has tried to push both sides toward compromise.

“I don’t have the answers. But to break this impasse the government needs to make the first move,” she said in a phone interview.

Many — including her — feel betrayed by Hong Kong’s leaders and increasingly angry at Beijing.

“If I knew what Hong Kong would be like today,” she said Wednesday, as hundreds of thousands took to the streets in a defiant plea for democracy, “I would not have been so enthusiastic 17 years ago in helping with the handover.”

“Today may be China’s National Day,” she said, “but for a lot of Hong Kong people, there’s very little for us to celebrate.”

Ishaan Tharoor in Hong Kong and Xu Jing in Beijing contributed to this report.