US concerned for 'missing' Chinese tennis player

The US government has expressed concern for a Chinese tennis player who apparently went missing after writing a social media post containing accusations about a former senior Chinese official.

Peng Shuai has reportedly not been seen in public after she posted the sexual assault allegations against former vice premier Zhang Gaoli.

The post said Zhang sexually abused her, and that the pair later had an extramarital relationship.

White House Press Secretary Jen Psaki told reporters on Friday that the US government is deeply concerned by reports that Peng appears to be missing.

She said the government joins the calls for Chinese authorities to provide independent and verifiable proof of her whereabouts and that she is safe.

She said the government will continue to stand up for freedom of speech. She said Washington knows that China has zero tolerance for criticism and a record of silencing those who speak out, and it continues to condemn those practices.

Earlier, a spokesperson for the Office of the UN High Commissioner for Human Rights asked for a transparent investigation into Peng's allegations of sexual assault.

The head of the Women's Tennis Association hinted at the possibility of pulling tournaments out of China unless the tennis player is accounted for.