In this file photo taken on May 29, 2018, China s Peng Shuai hits a return against Serbia s Aleksandra Krunic during their women s singles first round match on day three of The Roland Garros 2018 French Open tennis tournament in Paris (AFP)
Peng posted her allegations on social media last month.
"Unfortunately, the leadership in China has not addressed this very serious issue in any credible way,'' WTA Chairman and CEO Steve Simon wrote in a statement distributed by the tour. "While we now know where Peng is, I have serious doubts that she is free, safe, and not subject to censorship, coercion, and intimidation.''
Simon repeated his call for a "full and transparent investigation _ without censorship'' into Peng's accusations.
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