Sam Wong remembers exactly when he deleted his Facebook account.
An hour before the clock struck midnight on July 1, Hong Kong officially adopted a new national security law imposed by Beijing.
Like many others living in the city, Wong only learned about the full details of the sweeping legislation after it was signed into law.
By the time it came into force, he decided that the moment had come for him to quit the social media platform.
The social service manager in his early 30s, who spoke under a pseudonym for fear of jeopardising his job, joins other Hongkongers who are scrambling to protect their online privacy in the face of the new legislation.
Under the law, offences of secession, subversion, terrorism and collusion with foreign forces carry maximum penalties of life imprisonment.
Furthermore, the rules authorise the police to search electronic devices believed to contain criminal evidence, and require social media platforms and internet service providers to assist law enforcement without a warrant, according to industry experts.