The Women's Tennis Association (WTA) has said it is even more concerned for the safety of Chinese player Peng Shuai after an email supposedly sent by her was published by Chinese state media.
China's state-run foreign broadcaster CGTN published an email it said was sent by Peng to WTA chief Steve Simon late Wednesday.
Peng publicly made allegations of sexual assault against top Chinese politician Zhang Gaoli, 75, earlier this month and has not been seen since.
In the message released by CGTN, Peng says the news about her "including the allegation of sexual assault, is not true" and "I'm not missing, nor am I unsafe."
According to the message, she has been "resting at home."
The screenshot posted by CGTN was met with suspicion from some observers as the cursor appeared to be visible in the text.
WTA chief Simon said the statement only served to raise his concerns about her safety and whereabouts.
Unable to reach Peng
"I have a hard time believing that Peng Shuai actually wrote the email we received or believes what is being attributed to her," he wrote.
He said he had tried to reach Peng, 35, numerous times through multiple means of communication, and had not been able to.
"The WTA and the rest of the world need independent and verifiable proof that she is safe," Simon said.
Peng had posted allegations against Zhang on Chinese social network Weibo. She wrote that she had an on-off relationship with him for years but also accused him of sexual assault, without providing any evidence. The post was subsequently removed.