Facebook, WhatsApp, Twitter and Google said Monday they have “paused” their processing of requests for user data from Hong Kong law enforcement agencies, days after Beijing’s controversial new national security law came into force in the territory.

WhatsApp is “pausing” reviews “pending further assessment of the impact of the National Security Law, including formal human-rights due diligence and consultations with human-rights experts,” a WhatsApp spokeswoman said.

Facebook, WhatsApp’s parent company, said that it had done the same, citing the company’s belief in “the right of people to express themselves without fear for their safety or other repercussions.”

Twitter also said in a statement that it had suspended such requests since last week. “Like many public interest organizations, civil society leaders and entities, and industry peers, we have grave concerns regarding both the developing process and the full intention of this law,” it said.

A Google spokesperson said that the firm had “paused production on any new data requests from Hong Kong authorities” and would “continue to review the details of the new law.”

Although Facebook, its products Whatsapp and Instagram, Twitter, Youtube and Google generate ad revenue from China, they are all blocked in the country, where authorities shutter any online platform where they do not have ultimate control of content. They have, however, historically been openly accessible in Hong Kong, which has so far existed outside of mainland’s “Great Firewall.”

But Hong Kong is facing a series of unknowns since the July 1 enactment of the new national security law, which has been met by unprecedented concerns about the future for freedom of speech in the financial hub.

The U.S. tech companies could end up in a clash with Beijing as China seeks to impose greater controls on Hong Kong’s Internet space through this new legislation.

The new law criminalizes secession, subversion, terrorism and collusion with foreign powers in sweepingly broad terms. The rules give authorities the ability to investigate, prosecute and punish locals and foreigners alike for anything that seems to promote subversion or “incite hatred” of the Chinese regime.

It also states the officials may ask the publisher, platform, host or network service provider of any “electronic messages” that “endanger national security” to remove or restrict access to them. Failure to comply can lead to fines and a year in prison.

In a transparency report for July to December of last year, Facebook said that it had received 241 information requests on 257 users or accounts from Hong Kong authorities, and had provided “some data” in 46% of those cases.

Chat apps that have made a name for themselves offering greater levels of encryption and security have also chimed in on the matter. London-based Telegram was the first to state that it did not intent to process Hong Kong data requests.

Meanwhile, encrypted chat app Signal, popular with Chinese dissidents and Hong Kong protestors, owned it peers: “We’d announce that we’re stopping too, but we never started turning over user data to the HK police. Also, we don’t have user data to turn over.”