China has formally arrested a Chinese-born Australian journalist on suspicion of supplying state secrets overseas, Australia’s foreign minister said Monday. The arrest of Cheng Lei last Friday starts an official criminal investigation and came six months after she was detained. Ms Cheng works for CGTN, the English-language channel of China Central Television. “The Australian government has raised its serious concerns about Ms Cheng’s detention regularly at senior levels, including about her welfare and conditions of detention,” Foreign Minister Marise Payne said in a statement. “We expect basic standards of justice, procedural fairness and humane treatment to be met, in accordance with international norms,” she added. Worsening bilateral relations since Australia called for an independent investigation into the origins of the coronavirus pandemic are suspected to be the cause of Cheng’s arrest. Her two young children were with family members in Melbourne, Australia. A month before she was detained on August 13, Australia warned its citizens of a risk of arbitrary detention in China. China dismissed the warning as disinformation. Before the last two journalists working for Australian media in China left the country in September, they were questioned by Chinese authorities about Cheng. Australian Broadcasting Corporation reporter Bill Birtles and <em>The Australian Financial Review</em>'s Michael Smith were told they were "persons of interest" in an investigation into Cheng. “I believe the episode was more one of harassment of the remaining Australian journalists rather than a genuine effort to try and get anything useful for that case,” Birtles said after returning to Sydney. Australia has criticised China for charging Chinese-Australian spy novelist Yang Hengjun with espionage. He has been detained since January 2019. Australian Karm Gilespie was sentenced to death in China last year, seven years after he was arrested and charged with attempting to board an international flight with more than 7.5 kilograms of methamphetamine. Some observers suspect that such a severe sentence so long after the crime was related to the bilateral rift. Cheng was an anchor for CGTN's <em>BizAsia</em> programme. She was born in China and worked in finance in Australia before returning to China and starting a career in journalism with CCTV in Beijing in 2003.