HONG KONG, April 2, 2025 (BSS/AFP) - Hong Kong's new police chief on Wednesday stressed the need to protect national security following US sanctions on his predecessor and five other officials over Beijing's crackdown on human rights.

The United States on Monday imposed sanctions on officials accused of eroding Hong Kong's autonomy and "acts of transnational repression" -- referring to the city's use of national security laws to "intimidate, silence and harass" activists abroad.

Hong Kong authorities have condemned the sanctions and defended their use of the laws, while Beijing has vowed "countermeasures".

Police commissioner Raymond Siu, one of the six people sanctioned, retired on Tuesday after nearly four years in charge.

His replacement Joe Chow, 52, said he was not worried about the sanctions and that national security was the "most important" priority.

"The US sanctions are barbaric acts attempting to intimidate... police officers, so that we will stop working hard on national security," Chow told reporters on Wednesday.

"This shows that (the United States) considers our actions to be successful and effective. This means we should do more of it."

Chow, who joined the force in 1995, is best known for overseeing the police siege of Hong Kong's Polytechnic University in November 2019 at the height of the mass pro-democracy protests.

That operation saw the most violent clashes between protesters and police and ended with 1,377 arrests.

Beijing has since quashed dissent in Hong Kong using a sweeping national security law it imposed on the city.

Using powers under the security law, authorities have placed bounties on a total of 19 overseas democracy advocates since 2023, while scores of opposition figures have been arrested and jailed in Hong Kong.

Some of the named activists -- including UK-based Tony Chung and Carmen Lau and Australia-based Ted Hui and Kevin Yam --- last month reported being targeted by anonymous letters promising hefty rewards for people who inform on them.

Hong Kong officials have denied any involvement in the letters.

Chow told AFP the bounties were a "very sensitive" matter and declined to say if more were in the pipeline.

At the news conference, he said Hong Kong society had returned to stability but there were still "undercurrents everywhere" and warned of "soft resistance" via the arts, culture and media sectors.

Asked if more public protests will be permitted under his tenure, Chow said it depended on event specifics and added that police would conduct threat assessments.