Chinese-Australian writer Yang Hengjun (left) pictured with prominent liberal intellectual Mao Yushi in an undated photo.
Hong Kong CNN  — 

Chinese-Australian writer Yang Hengjun has been detained by Chinese authorities for alleged espionage, the family’s lawyer told CNN Thursday.

According to lawyer Mo Shaoping, Yang’s family had received a written notice from Beijing’s State Security Bureau confirming the writer’s detention.

Mo said he would be filing a petition to meet his client but wasn’t sure if it would be allowed due to the nature of the charges against Yang.

The Australian Department of Foreign Affairs and Trade said in a statement it would continue to seek confirmation as to why Yang had been taken and would attempt to obtain consular access to him “as a matter of priority.”

Australia’s Defense Minister Christopher Pyne, who was visiting Beijing on Thursday, said he would raise the matter with his counterpart Wei Fenghe during their meeting.

Yang, 53, is novelist and writer who previously worked as an official with the Chinese foreign ministry.

Though Yang holds Australian citizenship, he is known to spend most of his time in the United States, where he is a visiting scholar at Columbia University in New York.

Yang had made a trip back to China from New York with his wife on January 17 to pick up his stepdaughter’s US visa, family friend Watson Meng told CNN.

Meng said he tried to get in touch with Yang on social media the day after he arrived, but noticed he hadn’t read the posts days later. He then said he learned Yang had been detained through sources in the security department.

Yang has an active Twitter account with more than 130,000 followers, to which he routinely posts satirical commentaries that are critical of the Chinese government.

During a regular press briefing Thursday, Chinese Ministry of Foreign Affairs spokeswoman Hua Chunying confirmed Yang had been detained for allegedly endangering China’s national security. She said his legitimate rights and interests would be fully guaranteed.

Australian authorities couldn’t confirm the date Yang was taken in custody, or where he was being held.

Relations between Australia and China had been slowly warming after a deep chill in early 2018 following Canberra’s drafting of strict foreign interference laws, which officials in Beijing believed were targeted at China.

But a decision by the Australian government in August to ban 5G technology manufactured by Chinese company Huawei pushed relations back onto a precarious footing.

Australian Foreign Minister Marise Payne said Thursday there was “no evidence” of a connection between Yang’s arrest and Huawei’s global troubles.

“I would be concerned if there was an indication of that. So we are calling on the Chinese authorities to ensure this matter is dealt with transparently and fairly,” she said.

Elsewhere Beijing has been cracking down on individuals it views as a threat to the Chinese government, including labor activists, human rights lawyers and international bloggers.

Yang has a complicated history with Beijing, owing to his background as a former government official. He is known to have vanished in China once before, in the spring of 2011. Although it was widely speculated he was detained by Chinese state security agents, he never confirmed it upon re-appearing.

John Garnaut, Australian journalist and former prime ministerial adviser, wrote in a column Thursday that “the ground for everyone in China is shifting fast beneath our feet.”

“If the system has swallowed this hugely popular commentator … are there no longer any limits?”

CNN’s Serenitie Wang contributed to this article.