Hong Kong and China's flags were raised to mark the handover of the city from Britain 23 years ago Wednesday (1 July), just hours after a contentious new security law came into force.
It will mean up to life in prison for those convicted of crimes of secession, subversion, terrrorism and collusion with foreign forces.
The new law will supersede existing Hong Kong laws where there is a conflict and interpretation powers of the law belong to Beijing.
Judges for security cases will also be appointed by the city's leader.
Today, that's Chief Executive Carrie Lam, who said the law was the most important development since Hong Kong's return to Beijing.
"It is a historical step to perfect Hong Kong safeguarding national security, territorial integrity and a secure system. It is also an inevitable and prompt decision to restore stability in the society."
Authorities in Beijing and Hong Kong have repeatedly said the legislation is aimed at a few "troublemakers" and will not affect rights and freedoms.
Critics fear the legislation will crush wide-ranging freedoms in Hong Kong denied to people in mainland China that are seen as key to its success as a global financial center.
More than a dozen protesters gathered outside, calling for the law to be boycotted.
Ousted lawmaker "Long Hair" Leung Kwok-hung was there rallying with Avery Ng secretary General of League of Social Democrats:
"Probably in the future we may never see a million people on the street again, not because we are satisfied with the government but because we are now living in fear. But I still have hopes and do believe in Hong Kong especially the younger generation that will keep on fighting, despite the police ban, or even despite the national security law."
Authorities have barred an annual handover march set to be held later on Wednesday.
They cite a ban on gatherings of more than 50 people as part of social distancing limits.
Last year's July 1 march ended with hundreds storming the city's legislature to protest a now-scrapped bill that would have allowed extradition to mainland China.
It evolved into calls for greater democracy... and paved the way for Beijing to directly impose the national security law on the city.
Local media has reported that on Wednesday - up to 4,000 police officers would be deployed to stamp out any big protests.