BEIJING • China has said it had a right to put out its own views after Twitter and Facebook said they had dismantled a state-backed social media campaign originating in mainland China that sought to undermine protests in Hong Kong.

Twitter said on Monday that it has suspended more than 200,000 accounts that it believes were part of a Chinese government influence campaign targeting the anti-government protest movement in Hong Kong. Twitter also said it will ban advertisements from state-backed media companies, expanding a prohibition it first applied in 2017 to two Russian entities.

The accounts were suspended for violating the social networking platform's terms of service and "because we think this is not how people can come to Twitter to get informed", a senior company official told the Associated Press.

The official, who spoke on condition of anonymity because of security concerns, said the Chinese activity was reported to the Federal Bureau of Investigation, which investigated Russian efforts to interfere in the 2016 US presidential election through social media.

After being notified by Twitter and conducting its own investigation, Facebook said on Monday that it has removed seven pages, three groups and five accounts, including some portraying protesters as cockroaches and terrorists.

Twitter traced the Hong Kong campaign to two fake Chinese and English Twitter accounts that pretended to be news organisations based in Hong Kong, where protesters have taken to the streets since early June calling for the withdrawal of a controversial extradition Bill and for greater democracy.

The Chinese language account, HKpoliticalnew, and the English account, ctcc507, pushed tweets depicting protesters as violent criminals. One of those accounts was tied to a suspended Facebook account that went by the same moniker, HKpoliticalnew.

Foreign Ministry spokesman Geng Shuang, when asked about the matter at a daily briefing yesterday, defended the right of Chinese people and media to make their voices heard over the Hong Kong protests. Overseas Chinese and students "of course have the right to express their point of view", he said.

"What is happening in Hong Kong, and what the truth is, I think, the world will naturally make their own judgment," he said.

"Why must the descriptions by Chinese official media be definitely negative or wrong, you should ask Twitter about this. Chinese media uses foreign social media to reach people overseas and introduce China's policies to them and tell stories about China. I think this very reasonable," he said. "I don't know why some companies or some people have such a strong reaction to this."

Twitter and Facebook are blocked by the Chinese government from being used in the mainland.

Dr James Lewis of the Centre for Strategic and International Studies said the Twitter campaign reflects the fact that the Chinese government has studied the role of social media in mass movements and fears the Hong Kong protests could spark wider unrest.

Free speech organisation PEN America's chief executive Suzanne Nossel said: "China's government has denied its citizens access to global outlets for communication. That they now turn around and stealthily unleash a campaign of disinformation on the very same platforms represents a new height of hypocrisy."