China’s top official in Hong Kong said the city’s authorities should be vigilant against anti-Chinese forces and continue to “rigorously enforce” the national security law, suggesting no let-up in the crackdown on dissent.

There are still “hostile foreign forces” trying to disrupt Hong Kong’s development and stability, while “anti-China elements” are attempting a comeback, Zheng Yanxiong was cited as saying in local reports. The head of China’s Liaison Office in Hong Kong was speaking to officers at a police college on Saturday.

Zheng called on the officers to “build a solid defense line” for national security.

Beijing imposed the national security law on Hong Kong in June 2020 in response to the previous year’s mass protests against the government, which fostered anti-China sentiment.

Authorities in Hong Kong and China have signaled national security is still a top priority in the Asian hub. In July, officials placed a HK$1 million ($127,750) bounty on eight overseas activists, alleging they had committed offenses under the national security law even after leaving Hong Kong.

The US State Department decried the move, saying extraterritorial applications of the law “is a dangerous precedent,” that threatens people rights and freedoms.

More than 270 individuals have been arrested by national security police, while dozens including pro-democracy activists and former opposition lawmakers are facing charges under the law which carries a sentence as life-long imprisonment.