Chinese-born Australian academic Yang Hengjun was formally arrested in China on suspicion of espionage, Australia's government confirmed on Tuesday, Deutsche Welle reports.
Australian Foreign Minister Marise Payne said in a statement that her government was "very concerned and disappointed" by Yang's arrest in the southern city of Guangzhou in January. He was later transferred to Beijing.
"Dr. Yang has been held in Beijing in harsh conditions without charge for more than seven months," Payne said.
"Since that time, China has not explained the reasons for Dr. Yang's detention, nor has it allowed him access to his lawyers or family visits," she said.
"We expect that basic standards of justice and procedural fairness are met," Payne stressed.
"If Dr. Yang is being held for his political beliefs, he should be released," she added.
Read more:
A former Chinese diplomat turned online journalist and blogger, Yang has written pro-democracy and human rights articles and blogs on social media that have a considerable following in China.
China's foreign ministry has said the Australian academic was suspected of engaging in criminal activities that represented a danger to China's security.
But Yang's lawyer, Rob Stary, said it was still unclear why he had been charged with espionage.
"We think it relates to espionage on behalf of Australia, but it's not specified on the charge sheet," Stary said.
"We'd obviously be disturbed by that if it was the allegation because there is absolutely no foundation for it at all," he added.