Nov 19 (Reuters) - China"s Peng Shuai, a former doubles world number one, has not been seen in public since she accused a former vice-premier of the country, Zhang Gaoli, of sexual assault in a social media post that was deleted half an hour later. Following are reactions from the tennis community who are concerned about her whereabouts (on Twitter unless stated): WTA CHAIRMAN STEVE SIMON "The statement released today by Chinese state media concerning Peng Shuai only raises my concerns as to her safety and whereabouts," Simon said in a written statement. "I have a hard time believing that Peng Shuai actually wrote the email we received or believes what is being attributed to her." ATP CHAIRMAN ANDREA GAUNDEZI "Developments in recent days in the case of Peng Shuai are deeply unsettling. The issue is bigger than tennis as shown by the outpouring of concern within and beyond our sport. Her safety is our immediate concern and clarity is required on the situation. The need for verifiable direct communication with her is vital." SERENA WILLIAMS, 23-TIMES GRAND SLAM CHAMPION "I am devastated and shocked to hear about the news of my peer, Peng Shuai. I hope she is safe and found as soon as possible. "This must be investigated and we must not stay silent. Sending love to her and her family during this incredibly difficult time." WORLD NUMBER ONE NOVAK DJOKOVIC "Honestly, it"s shocking that she"s missing, more so that it"s someone that I have seen on the tour in the previous years quite a few times," Djokovic said at the ATP Finals. "It"s not much more to say than hope that she will be found, that she"s okay. It"s terrible... I can imagine just how her family feels that she"s missing." PROFESSIONAL TENNIS PLAYERS ASSOCIATION (PTPA) "The Professional Tennis Players Association (PTPA) is advocating for independent evidence confirming the safety and location of WTA player, Peng Shuai. "We must unite and be willing to take action unless corroborated evidence is provided to the world about Peng"s well being." FOUR-TIME GRAND SLAM WINNER NAOMI OSAKA "I was recently informed of a fellow tennis player that has gone missing shortly after revealing that she has been sexually abused. Censorship is never OK at any cost, I hope Peng Shuai and her family are safe and OK." INTERNATIONAL OLYMPIC COMMITTEE "Experience shows that quiet diplomacy offers the best opportunity to find a solution for questions of such nature," an IOC spokesperson said. "This explains why the IOC will not comment any further at this stage." PARIS 2024 OLYMPIC GAMES CHIEF TONY ESTANGUET "We did the Games in Beijing and London together. Today, like the entire sporting community, I am concerned about Peng Shuai. We appeal for the greatest transparency in this situation." TENNIS HALL OF FAME "The recent events surrounding Peng Shuai are deeply troubling. The International Tennis Hall of Fame shares in concern for her well-being and in the call for an assurance of her safety." TWO-TIMES WIMBLEDON CHAMPION PETRA KVITOVA "The news about Peng Shuai is deeply upsetting. I want to lend my voice of support to an incredibly courageous fellow WTA player and pray that she is found safe and well." FRENCH PLAYER ALIZE CORNET "Watching the whole tennis community, and now the whole world, getting involved into Peng Shuai"s story gives me hope somehow. I just can"t wait to know that she is safe and healthy. We need to know. In the meantime, let"s stand together." FORMER WORLD NUMBER ONE SIMONA HALEP "Peng Shuai, please know that your fellow players stand with you. Thinking of you and hope you are safe." AMERICAN PLAYER COCO GAUFF "Sending prayers and hoping you are safe. #WhereIsPengShuai"