Li Xin, a writer for the cutting-edge newspaper, fled to New Delhi last October after being recruited by China's state security police to spy on other activists, with the threat of spying charges hanging over him.
The formerly active campaigner for democratic reform and human rights said authorities pressured him to become an informant after he posted comments online in support of blind Shandong rights activist Chen Guangcheng.
After arriving in India, Li made public confidential documents from his time at the newspaper, revealing the inner workings of the ruling Chinese Communist Party's propaganda machine, which included a secret list of topics and sources off limits to media outlets.
Li could not be granted political asylum in India, because the country does not accept applications from Chinese nationals. He then applied for a tourist visa at the American embassy in New Delhi so he could go to the United States and apply for asylum there, but his application was rejected.
Li traveled to Thailand on Jan. 1 and boarded a train nine days later to the northeastern border town of Nong Khai where he tried to enter Laos, but suddenly lost contact with his wife Shi Sanmei, she told RFA's Mandarin Service.
A friend tried to report the case to the Thai police, but the report was rejected, she said.
"They asked, 'Why you didn't you report this to the Chinese embassy," said Shi, who remains in China.
"But I am not in Thailand, so there is no way to get to the Chinese embassy," she said. "After all, I cannot leave, so I have no choice."
Lao authorities
If Shi cannot get any information about Li's disappearance from police in Thailand, she will try to get information from Lao authorities, she said.
"But now the situation is that Thai authorities have refused to accept Li's case, so how can I go to Laos?" Shi said.
Shi telephoned Li's family on Wednesday, hoping they had reported the disappearance to local police, but was unable to reach them, she said.
Later, Li's aunt told Shi that Li's father had received her message about the disappearance, Shi said.
"I requested that she accompany Li's father to report it to the police," she said.
Last December, authorities in the southern Chinese province Guangdong prevented Shi and the couple's infant son from leaving the country to join Li after his attempted defection.
Border officials in Shenzhen stopped the two as they tried to cross into neighboring Hong Kong, which has maintained its own internal immigration border since its 1997 handover to Chinese rule.
At the time, Li said he believed authorities slapped the exit ban on his wife and child as a form of retaliation after he leaked information about the inner workings of the Chinese government's propaganda machine.