In March, she wrote a Facebook status describing a censored, viral magazine profile of a doctor at Wuhan’s Central Hospital, who said she was reprimanded for raising the alarm about coronavirus.
“The article lived for a few hours, and then the purge started,” she wrote.
Weeks earlier, on 27 February, she shared another status referring to “the most circulated posts of the day”, which were investigative articles detailing cover-ups by local government authorities in Wuhan.
A number of citizen journalists in China were arrested earlier this year, and some are still missing, after publishing details of the coronavirus crisis in Wuhan.
Delia Lin, a senior lecturer in Chinese Studies at Melbourne University, said it is unlikely the Facebook posts were the catalyst for her detainment, given how much time has passed since they were published.
“Why her, why now? She hasn’t really done anything extraordinary. She’s not overly outspoken about the political situation in China,” Dr Lin, who is originally from Wuhan, told SBS News.
“She’s also known for reporting things that are favourable to Beijing, because she works for this TV station which requires her to be favourable in many of her reports and she’s done that genuinely without compromising her professional integrity.
“She certainly knows her boundaries very well, extremely well, and she’s never really crossed those boundaries as far as I can see.”
In her most recent Tweet on 12 August, two days before the Australian government was notified of her arrest, Ms Cheng shared a celebratory video of a new Shake Shack store opening in Beijing.
The targeting of Ms Cheng sent a “chilling message” for other Australians working in China that they too could face repercussions, even if they are not outspoken about their views, Dr Lin said.
‘A really great bridge between China and Australia’
Ms Cheng had worked at CGTN for eight years before her arrest, following stints at CNBC Asia in Singapore and China and at CGTN’s predecessor CCTV News.
Her journalism profile on CGTN has since been removed from their website.
“She is known to be a really great bridge between China and Australia,” Dr Lin said. “And is certainly someone who values her experience in Australia and tries to help both nations, and both peoples, to understand one another.”
Dr Lin said the arrest could be a message to the Australian government, which has been facing strained relations with China over recent months. “It does make people wonder, because it’s very unusual that it could be her,” she said.
Australian officials working with China to assist detained Australian journalist Cheng Lei
Fergus Hanson, director of the International Cyber Policy Centre at the Australian Strategic Policy Institute (ASPI) said on Tuesday that Ms Cheng’s arrest could fit into a pattern China attempting to use “arbitrary arrests, arbitrary executions, as a means to coerce states into changing their behaviour.”
“Is it a very effective strategy? No I don’t think so but it is a really brutal one,” he said, adding that more details were needed before the motivations behind the detention could be determined.
Speaking to ABC News on Tuesday, Education Minister Simon Birmingham said there were “clearly a number of issues” with the Chinese-Australian relationship, but did not elaborate on the reasons for Ms Cheng’s detention.
“We're working through details in terms of the consular assistance that we can provide, and we will give all assistance that we can,” he said.
Meanwhile, opposition treasury spokesperson Jim Chalmers described the arrest as “concerning” and said Labor was “as one with the government” in trying to resolve it.
It is understood Ms Cheng has not been formally charged and was being held under “residential surveillance”, a form of detention that allows authorities to hold a suspect for up to six months without formal arrest, ABC News reported.
Ms Cheng’s family have declined to speak to the media but released a statement which said they were aware of the arrest.