Top Chinese-language blogger and Australian national Yang Hengjun has resurfaced in China following fears that he might have been detained as part of a crackdown on outspoken netizens.
Yang, who was contacted by RFA's Cantonese service on Wednesday, three days after losing contact with friends and family in the southern Chinese city of Guangzhou, said he had been "unwell" during that time.
He declined to give further details, however, saying only: "Let's get in touch at a later date."
He said he would contact Australian officials. "I will give them an update," Yang said. "The [Chinese] foreign ministry has also clarified things," he added.
Australian officials expressed concern over Yang's fate after he told a friend he was being followed by three men in a Chinese airport on Sunday.
Nothing more was heard from him until Wednesday, sparking fears he might have been detained by national security police.
One of the most influential political bloggers writing in the Chinese language, Yang's posts reached millions of readers inside mainland China, where information is strictly controlled by a system of filters, blocks, and human censorship known as the Great Firewall, or GFW.
The Australian Foreign Affairs Department said on Monday it was "concerned" about reports of Yang's disappearance.
"The Australian consul-general in Guangzhou is urgently seeking to confirm the man's whereabouts and well-being and provide him with consular assistance if needed," a spokesman said.
Formerly employed by China's foreign ministry, Yang has published a spy novel called Fatal Weakness, depicting corruption and espionage in contemporary China.
Yang has said that three publishing companies withdrew their initial offers to publish it after coming under official pressure.
Yang's phone call came amid a nationwide clampdown on political expression in the wake of anonymous calls for a "Jasmine revolution" inspired by recent uprisings in the Middle East.
His friend, Feng Chongyi, an associate professor in China Studies at the University of Technology in Sydney, said Yang had given a pre-arranged signal that meant he had been detained by state security police.
Feng said he saw Yang's denial of detention as a likely condition of his release. Yang spends most of his time in China, although his wife and two children live in their Sydney home.
"It's my guess that the authorities just want the situation to calm down and then will let him walk away, but he has to deny that he was held by authorities until he leaves China," Feng was quoted by the AP as saying.
China's ruling Communist Party has launched a fresh wave of detentions and subversion trials in recent weeks.
Sichuan authorities recently detained activist and writer Ran Yunfei on charges of "incitement to subvert state power" and handed a 10-year jail term to writer Liu Xianbin on the same charges.
Sichuan-based political activists Ding Mao and Chen Wei have also been formally detained on subversion charges.
Reported by Ho Shan for RFA's Cantonese service, and by Ding Xiao for the Mandarin service. Translated and written in English by Luisetta Mudie.