Twitter has taken down thousands of accounts linked to China that were part of a "manipulative and coordinated" campaign to spread disinformation around topics including the Hong Kong protests and the coronavirus.
The social media site said that 23,750 accounts that were spreading "geopolitical narratives favorable to the Communist Party of China (CCP)" were removed. Another 150,000 accounts designed to boost that content were also taken down.
They were tweeting predominantly in Chinese languages and were pushing "deceptive narratives about the political dynamics in Hong Kong," Twitter said.
China's Ministry of Foreign Affairs was not immediately available for comment when contacted by CNBC.
The state-backed Twitter campaign highlights a shift in tactics from Beijing that have become more covert and akin to Russia's disinformation tactics online, according to the Australian Strategic Policy Institute (ASPI) think tank, which analyzed the recently taken down accounts.
Twitter's latest revelation appears to go against previous denials from China that it engaged in a disinformation spreading campaign on social media.
Protests in Hong Kong, China's response to the coronavirus outbreak and Taiwan are among the topics the state-backed accounts tweeted about.
"We have identified that this operation continues and has pivoted to try to weaponise the US Government's response to current domestic protests and create the perception of a moral equivalence with the suppression of protests in Hong Kong," ASPI said in its report.
Demonstrations in Hong Kong have been going on for more than a year. The people there have been protesting the proposed national security law from Beijing and the growing influence of the Chinese central government on the semi-autonomous city which enjoys certain freedoms that mainland Chinese are not given. Protesters have clashed with police, who sometimes used methods such as tear gas to disperse the crowds.
Meanwhile, the U.S. protests were sparked by the killing of George Floyd, an unarmed black man, at the hands of Minneapolis police. Protesters, who are campaigning for equal treatment of Black people, have also clashed with police.
The accounts that Twitter took down also focused on China's response to Covid-19.
"The tweets in this set focused on cheering on the Chinese government epidemic response, calling for Chinese and global unity, painting China as a responsible stakeholder in the international environment," according to Stanford Internet Observatory (SIO), which analysed the removed accounts.
It is not the first time Twitter has acted against Chinese state-backed accounts.
In August last year, the social media firm and its rival Facebook removed accounts they said were spreading disinformation regarding the protests in Hong Kong at the time.
Ultimately, the accounts "were largely caught early and failed to achieve considerable traction on the service, typically holding low follower accounts and low engagement," Twitter said.
But the trend of Beijing spreading disinformation using western social media platforms, which are blocked in China, is likely to continue.
"This large-scale pivot to Western platforms is relatively new, and we should expect continued evolution and improvement, given the enormous resourcing the Chinese party-state can bring to bear in aligning state messaging across its diplomacy, state media and covert influence operations," ASPI said.
"The disruption caused by Covid-19 has created a permissive environment for the CCP to experiment with overt manipulation of global social media audiences on Western platforms," it added.
Separately, Twitter also said it took down a few thousand accounts linked to Russia and Turkey.