This article contains references to sexual assault.
Serena Williams has joined the calls for an investigation into the welfare of Chinese tennis star Peng Shuai.
The 23-time grand slam champion is the latest in a growing number of players and organisations to express concern about the safety of the 35-year-old, who has not been seen since making allegations of sexual assault against a former Chinese government official two weeks ago.
An email purporting to be from the Chinese player was published by Chinese state media on Thursday, before quickly being removed as concerns continue to mount.
"I am devastated and shocked to hear about the news of my peer, Peng Shuai," Williams wrote on Twitter.
"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."
Head of the Women's Tennis Association Steve Simon has insisted Peng's voice must be heard, suggesting the issue could jeopardise the tour's future in China despite the huge sums of money at stake.
"I have repeatedly tried to reach her via numerous forms of communications, to no avail," he said in a statement.
"Peng Shuai 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."
If you or someone you know is impacted by family and domestic violence, call 1800RESPECT on 1800 737 732 or visit . In an emergency, call 000.
