One year after China imposed a draconian national security law on Hong Kong, police locked down Victoria Park, a former site of mass protest rallies and marches, and cordoned off downtown streets, while supporters of the ruling Chinese Communist Party (CCP) hung flags along the streets and sang revolutionary songs.

Dozens of police in Causeway Bay surrounded and arrested veteran protester Alexandra Wong, a frequent participant in the 2019 protest movement, for waving a British flag, photos posted to social media showed.

A young boy was also chased by officers through the Fashion Walk mall before being dragged aboard a police vehicle, photos posted to Twitter on the 24th anniversary of the 1997 handover to Chinese rule showed.

Bystanders said he had apparently been targeted for carrying a bag that was yellow, the color used by the pro-democracy movement and two mass protest movements since 2014.

Police also arrested three activists from the group Student Politicism in Mong Kok at around 5.00 p.m. local time, on suspicion of "distributing seditious publications," according to a police statement and social media reports.

And barrister Chow Hang-tung, who heads a group that once organized an annual candlelight vigil marking the June 4, 1989 Tiananmen massacre, was rearrested on suspicion of "inciting others to participate in an unauthorized assembly" under public order laws.

Hundreds of police took to the streets of Causeway Bay, arresting 19 people on suspicion of offenses that included "disorderly conduct," failing to heed police warnings, and "desecrating the national flag."

They also handed out 19 fixed penalties for breaches of a ban on gatherings linked to coronavirus restrictions.

Two women who were fined said they had only been in a group of two, when the maximum number allowed is four.

"We don't know how this happened. They pulled us to one side and said we had violated the gathering restriction order," a woman surnamed Ng told RFA. "There were just the two of us, nobody else."

"I don't know what the Hong Kong government is turning into."

Her friend, surnamed Lee, said she had been hit with a H.K.$5,000 fine "for no reason."

"We just came out to go shopping," she said. "I work hard as a cleaner and they just fine me H.K.$5,000 for no reason."

Protesters turn out in small groups

Despite a police ban on what had been an annual mass protest march on July 1, people turned out in small groups to chant slogans and wave flags and protest banners, police said in a statement on their Facebook page.

Later in the evening, a man allegedly stabbed a police officer in the district at around 10.00 p.m., the police said.

"The officer sustained injuries to the left side of his back and was sent to hospital for treatment, while the assailant was subdued on the spot," the statement said.

Rights groups hit out at the rapid deterioration of human rights protections since the national security law was imposed on Hong Kong by China's National People's Congress (NPC) standing committee.

Chinese and Hong Kong officials have said the law was needed to deal with an attempt by foreign powers to foment a "color revolution" in Hong Kong, a reference to the 2019 protest movement that began as mass, peaceful opposition to plans to allow extradition to mainland China.

But its sweeping provisions allowed China's feared state security police to set up a headquarters in Hong Kong, granted sweeping powers to police to search private property and require the deletion of public content, and criminalized criticism of the city government and the ruling Chinese Communist Party (CCP).

Dozens awaiting trial

Dozens of opposition lawmakers are awaiting trial for subversion for taking part in a democratic primary, while at least seven journalists have been arrested for "colluding with a foreign power" in connection with opinion pieces in the Apple Daily newspaper, which was forced to close after its assets were frozen in a raid by national security police on June 17.

"Since the law has gone into effect, [the] authorities have used it to drastically curtail freedom of expression and other human rights far beyond what international human rights law permits," the Chinese Human Rights Defenders (CHRD) network said in a joint statement with other rights groups.

"The Hong Kong government has accused the [Apple Daily] of publishing approximately 100 videos or articles that are suspected of violating the National Security Law while refusing to specify which videos and articles," it said.

Apple Daily founder Jimmy Lai is currently serving a 14-month sentence for participating in pro-democracy protests in August 2019 while awaiting trial for "colluding with a foreign power" under the national security law.

"Shutting down the city’s most popular Chinese language newspaper and detaining its staff is the most obvious and emblematic violation of the right to freedom of expression in Hong Kong today," CHRD said in the statement, that was signed by Safeguard Defenders and Humanitarian China, among other groups.

It also cited the government's assertion of editorial control over public broadcaster RTHK, where a number of prominent journalists have been fired or sanctioned for producing content critical of the authorities.

The groups also cited constraints on academic freedom at Hong Kong's universities, with events canceled, debates modified, and lecturers reported by student informants over potential violations of the law.

Targeting the opposition

Eric Lai, research fellow at the University of Georgetown law school, said it was clear that the government is using the law to target the political opposition, with the majority of arrests under the law being of opposition politicians.

He said the refusal to release national security suspects on bail had interfered with the presumption of innocence that was previously a feature of Hong Kong's common law jurisdiction.

"We can't see any sign that they are presuming innocence, because a large proportion of defendants aren't being released on bail," he said.

"They have also changed the trial system by abolishing jury trials [in national security cases]," Lai told RFA. "The point of a jury trial ... is to make the trial more fair and open, but they are taking the opposite approach."