The Hong Kong government marked the 22nd anniversary of the former British colony’s return to China on Monday, as police faced off with protesters outside the venue.
A flag-raising ceremony, in which the Chinese and Hong Kong flags are raised together, was held under unusually high security.
Police used riot shields and pepper spray to push back helmeted protesters who tried to advance down closed streets toward the city’s convention centre.
Hong Kong leaders, mainland China representatives and invited guests watched the ceremony inside instead of outside as they normally do.
The government cited inclement weather after light rain fell earlier in the morning.
City leader Carrie Lam said a series of protests that have attracted hundreds of thousands of students and other participants have taught her that she needs to listen better to the youth and people in general.
Ms Lam has come under withering criticism for pushing legislation that would have allowed suspects to be extradited to mainland China to face trial.
“This has made me fully realise that I, as a politician, have to remind myself all the time of the need to grasp public sentiments accurately”, she said in a five-minute speech to the gathering.
She insisted the government has good intentions, but said: “I will learn the lesson and ensure that the government’s future work will be closer and more responsive to the aspirations, sentiments and opinions of the community.”
Security guards pushed a pro-democracy politician out of the room as she shouted at Ms Lam to resign.
A march planned for Monday afternoon is expected to be larger than usual because the extradition bill has awakened broader fears that China is eroding Hong Kong’s freedoms.
Two earlier marches against the legislation drew more than a million people, according to estimates from organisers.