Hong Kong on Thursday marked the 24th anniversary of its handover from Britain to China amid a heavy police presence to prevent pro-democracy protesters from gathering despite a ban on such an activity.

Police sealed off sections of Victoria Park at noon, citing rumored plans for unauthorized assembly that were circulated online. According to media reports, 10,000 officers were deployed throughout the city, over double the number last year.

China's national flag is hoisted during a ceremony in central Hong Kong on July 1, 2021, to mark the 24th anniversary of the city's handover from Britain. (Kyodo)

Thursday also marked the 100th anniversary of the founding of the Chinese Communist Party.

At a flag-raising ceremony held at Golden Bauhinia Square, newly appointed Chief Secretary for Administration John Lee said the implementation of the national security law a year ago has returned Hong Kong to order from chaos.

Lee gave remarks in place of Chief Executive Carrie Lam, who was attending the coinciding anniversary celebration in the capital Beijing.

Earlier this week, Hong Kong police banned the annual July 1 pro-democracy rally, citing public health concerns during the coronavirus pandemic.

In a press briefing held at Victoria Park on Thursday, police warned that those who participate in the assembly would be in violation of the Public Order Ordinance, punishable by up to five years in prison.

This marked the second consecutive year that the rally has been banned by the authorities. Despite the ban, over 10,000 people participated last year, partly to express opposition to the just-enacted national security law.

The law, which came in the aftermath of the sometimes violent 2019 pro-democracy protests, criminalizes acts of secession, subversion, terrorism and collusion with foreign forces.

The law's implementation has resulted in the arrests of over 100 pro-democracy activists. Critics say the law has been used by authorities to suppress freedoms in the city.

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