Twitter helped to promote Chinese government propaganda and disinformation about the country’s controversial internment camps in the Xinjiang region, a review of the company’s advertising records reveals.

The social media company today announced a policy change that would bar such promotion following an inquiry from The Intercept and an earlier controversy over similar propaganda related to demonstrations in Hong Kong.

In Xinjiang, a western province in China, the United Nations has estimated that 1 million ethnic minority Muslim Uighurs — including children, pregnant women, elderly people, and people with disabilities — have been detained under the pretext of fighting extremism. According to Human Rights Watch, Chinese authorities are “committing human rights abuses in Xinjiang on a scale unseen in the country in decades.”

A review of Twitter advertisements from between June and August this year showed that the social media giant promoted more than 50 English-language tweets from the Global Times, a Chinese state media organization. Several of the tweets deliberately obscure the truth about the situation in Xinjiang and attack critics of the country’s ruling Communist Party regime.

The Global Times paid Twitter to promote its tweets to a portion of the more than 300 million active users on the social media platform. The tweets appeared in users’ timelines, regardless of whether they followed the Global Times account. In July, amid global condemnation of the treatment of Uighurs in Xinjiang, Twitter began promoting several Global Times tweets about the region.

One of the promoted tweets, from July 11, included a embedded video in which the Global Times’ editor-in-chief claimed that people who refer to the facilities in Xinjiang as “mass detention camps” have “smeared the vocational education and training centers established to help people avoid extremism.” He went on to attack “European politicians and media workers,” who he claimed had “tried to defend terrorist activities in Xinjiang,” adding, “their hands are in a way soiled with the blood of the Chinese people who died in violent attacks.”

Another promoted tweet, from July 4, included a video purportedly taken in Xinjiang, in which people are seen shopping in the street and eating in restaurants to a soundtrack of piano music. The video describes riots in 2009 that occurred in Urumqi, the capital of Xinjiang, and states that residents there “now live a happy and peaceful life” because they work together to fight terrorism and extremism. There is no mention in the video of the mass detention camps.

“Twitter is helping to promote false allegations and government propaganda. Allowing such advertising sets an alarming precedent.”

Other Global Times ads promoted by Twitter follow a similar theme, presenting the region as a happy and peaceful place where no human rights abuses have occurred. One promoted tweet includes video of an elderly woman receiving a package of medical supplies from government officials before breaking down in tears of joy. The tweet claims that poverty has been alleviated in the area because local residents have “access to high-quality medical care and affordable medicines.”

Patrick Poon, China researcher for Amnesty International, said he found Twitter’s promotion of the advertisements to be “appalling.”

“This is a very important, serious issue that Twitter needs to address,” said Poon. “Twitter is helping to promote false allegations and government propaganda. Allowing such advertising sets an alarming precedent.”

On Monday, Twitter said that it would no longer accept advertising from state-controlled media, in order to “protect healthy discourse and open conversation.”

The announcement was published three hours after The Intercept had contacted the company for comment on its promotion of the Global Times’ Xinjiang tweets. Earlier on Monday, TechCrunch highlighted Twitter’s promotion of tweets from a different state news entity, China Xinhua News, which portrayed largely peaceful pro-democracy demonstrations in Hong Kong as violent.

Twitter’s promotion of Chinese government propaganda had appeared to contradict its own policies, which state that advertising on the platform must be “honest.” The advertisements also undermined statements from Twitter CEO Jack Dorsey, who told the Senate Intelligence Committee last year that the company was working to combat “propaganda through bots and human coordination [and] misinformation campaigns.”

Like many Western technology companies, Twitter has a complex relationship with China. The social media platform is blocked in the country and cannot be accessed there without the use of censorship circumvention technologies, such as a virtual private network or proxy service. At the same time, however, Twitter generates a lot of advertising revenue in China and has a growing presence in the country.

In July, Twitter’s director in China reportedly stated that the company’s team there had tripled in the last year and was the company’s fastest growing division. In May, the social media giant held a “Twitter for Marketers” conference in Beijing. Meanwhile, Twitter was criticized for purging Chinese dissidents’ accounts on the platform – which it claimed was a mistake – and has also been the subject of a protest campaign, launched by the Chinese artist Badiucao, after it refused to publish a “hashflag” symbol to commemorate the 30th anniversary of the Tiananmen Square massacre.

Poon, the Amnesty researcher, said police in China have in recent months increasingly targeted human rights advocates in the country who are active on Twitter, forcing them to delete their accounts or remove specific posts that are critical of the government. These cases have been reported to Twitter, according to Poon, but the company has not taken any action.

“Twitter has allowed the Chinese government to advertise its propaganda while turning a deaf ear on those who have been persecuted by the Chinese regime,” Poon said. “We need to hear how Twitter can justify that.”