New Delhi, Nov 18 (IANS): The Women's Tennis Association (WTA) has cast doubts on an email released by the Chinese state media attributed to tennis player Peng Shuai who has levelled sexual assault allegations against a former Vice Premier.

Steve Simon, WTA Chairman and CEO said: "The statement released today by Chinese state media concerning Peng Shuai only raises my concerns as to her safety and whereabouts.

"I have a hard time believing that Peng Shuai actually wrote the email we received or believes what is being attributed to her. Peng Shuai displayed incredible courage in describing an allegation of sexual assault against a former top official in the Chinese government. The WTA and the rest of the world need independent and verifiable proof that she is safe. I have repeatedly tried to reach her via numerous forms of communication, to no avail."

Simon said Peng must be allowed to speak freely, without coercion or intimidation from any source. Her allegation of sexual assault must be respected, investigated with full transparency and without censorship.

"The voices of women need to be heard and respected, not censored nor dictated to," Simon said.

A growing movement including Chinese feminist groups and international tennis stars is raising concern over the whereabouts of the former Chinese doubles pro Peng after she accused a senior government figure of sexual assault, The Guardian reported.

Peng, one of China's biggest sporting stars, has not been publicly heard from since a Weibo post on November 2, in which she alleged the former Vice Premier Zhang Gaoli coerced her into sex and that they had an intermittent affair, the report said.

The post was taken down by China's censors but still went viral. Subsequent posts and reactions, even keywords such as "tennis", also appeared to be blocked, and numerous references to Peng were scrubbed from China's internet.

The WTA has sought a "full, fair and transparent investigation" into sexual assault allegations against former Chinese leader.