Australia is investigating reports a Chinese dissident with Australian citizenship has gone missing in China and may have been detained in his native country, officials have said.

Yang Hengjun, a novelist who was once a Chinese diplomat, went missing shortly after he returned to the southern city of Guangzhou last week, friends said.

When asked about Yang's case, the Australian Department of Foreign Affairs and Trade said on Wednesday it was "seeking information about an Australian citizen who has been reported missing in China".

"Owing to our privacy obligations we will not provide further comment," a spokesman told AFP news agency.

The Australian government is believed to be in contact with Yang's friends and family, as well as Chinese authorities.

The Sydney Morning Herald reported that Yang had returned to China with his wife and son on January 18, but failed to board a planned domestic flight to Shanghai, in east-central China.

His disappearance prompted fears that he may be the latest critic to be detained by Chinese security services.

Spate of detentions

Australia recently expressed concern about China's detention of two Canadians in apparent retaliation for the arrest in Canada of a senior Huawei executive. 

Meng Wanzhou, the chief financial officer of the telecommunications giant, was arrested in Canada on December 1 and the United States said on Tuesday it would seek her extradition to have charges over the company's alleged dealings with Iran. 

Yang's friend and journalist John Garnaut described him as "brilliant" and "a courageous and committed democrat".

"This will reverberate globally if authorities do not quickly find an off-ramp," he said.

Yang had worked in China's Ministry of Foreign Affairs in the southern province of Hainan, but in 1992 moved to Hong Kong, which was then a British colony. Five years later, he went to the US where he worked for the Atlantic Council think-tank.

Yang later took up Australian citizenship and wrote a series of spy novels as well as a popular Chinese-language blog.

Once described as China's "most influential political blogger", Yang went missing in 2011. When he reappeared days later, he described his disappearance as a "misunderstanding".