Some social media giants will temporarily stop processing requests for user data from Hong Kong authorities as a new security law recently enacted in the territory brings harsher punishment for online dissent.
Twitter, Facebook and WhatsApp say they will shelve user data requests from Hong Kong law enforcement agencies.
“We believe freedom of expression is a fundamental human right and support the right of people to express themselves without fear for their safety or other repercussions,” Facebook said.
Telegram, which is widely used in Hong Kong, said it would stop processing “any data requests related to its Hong Kong users until an international consensus is reached in relation to the ongoing political changes in the city".
The Hong Kong national security bill was introduced by Beijing and rapidly pushed into law last week.
It gives China a new degree of control over Hong Kong affairs and effectively strips the territory of its legal autonomy.
The law, which follows anti-government protests in Hong Kong last year, makes secessionist, subversive and terrorist activities illegal, as well as foreign intervention in the territory’s internal affairs.
Activity such as shouting slogans or holding up banners and flags calling for the Hong Kong's independence are breaches of the law regardless of whether violence is used.
The maximum penalty is life imprisonment.
Critics regard it as Beijing’s boldest step yet to dismantle the policy of one country, two systems that rules the former British colony.
On Monday, the Hong Kong government revealed new details of the law, which grant sweeping powers to police.
It allows police to conduct searches at private properties without a warrant, intercept communications and force internet service providers to remove information from their platforms.
The law states that if an “electronic message” is deemed damaging to national security, law enforcement officials can request the message be removed, restrict all access to it, or restrict all access to the platform on which it was posted.
“If the publisher fails to co-operate immediately,” the law states, authorities can apply for a warrant to seize the electronic device and “take any action for removing that information".
Publishers who refuse to remove messages “endangering national security” could face a $100,000 fine and up to six months in prison.
Unlike China, Hong Kong has an open internet system and has not blocked access to social media.
Telegram has been the favoured platform for communications between Hong Kong protesters because of its encrypted security features.
It can also host groups that effectively serve as notice boards, where members cannot post but can stay updated on information.
The groups can share information ranging from protest strategies and police locations to protest-inspired art pieces.
"We understand the importance of protecting the right to privacy of our Hong Kong users under these circumstances," Mike Ravdonikas of Telegram told the Hong Kong Free Press.
Telegram confirmed it has “never shared any data with the Hong Kong authorities".
Last summer, during the peak of extradition bill protests, the administrator of a Telegram group sharing information about the protests was arrested on public nuisance charges.
Ivan Ip, 22, said after his arrest that police had demanded he unlock his phone and transfer all his data from Telegram, including member lists and chat records.
Another administrator closed the Telegram group to protect its members.
Mr Ip’s arrest prompted other Telegram groups to warn their users to buy pre-paid Sim cards or register foreign numbers to join.
Other major online platforms, such as Google, have not commented on whether the security law will affect their operations in Hong Kong.