"We're in every corner of society, watching, to see if there is anything suspicious which could infringe on the national security law," former banker Innes Tang tells the BBC World Service. "If we find these things, we go and report it to the police."
When the UK returned Hong Kong to China 28 years ago, internationally binding treaties guaranteed the city's rights and freedoms for 50 years. But the national security law (NSL), imposed by Beijing a year after Hong Kong's 2019 mass pro-democracy protests, has been criticised for scuttling free speech and press, and for ushering in a new culture of informing. The law criminalises activities considered to be calls for "secession" (breaking away from China), "subversion" (undermining the power or authority of the government), and collusion with foreign forces.
