Minnie Chan, a reporter with Hong Kong-based South China Morning Post (SCMP) specialising in defence and diplomacy issues in China, "became unreachable" after visiting Beijing to cover the Xiangshan Forum in late October, Japanese news agency Kyodo said, citing her friends.

The Hong Kong Journalists Association said on Friday it was "very concerned about Minnie Chan's safety and is asking South China Morning Post to learn more."

It also urged relatives and friends to reach out with more information.

SCMP told AFP later Friday that Chan "has taken personal leave" and that the paper was in contact with her family.

"Her family has informed us that she is in Beijing but needs time to handle a private matter," the news outlet said in an emailed statement.

"Her family has told us she is safe but has requested that we respect her privacy."

Chan did not respond to AFP's request for comment.

Asked about the Kyodo report on Friday, Beijing foreign ministry spokesperson Wang Wenbin said he was "not aware" of the case.

According to the Hong Kong broadsheet's website, Chan's most recent articles were from the Xiangshan Forum, which ended on October 31.

She also wrote about the Chinese military's overhaul and the abrupt sacking of Chinese defence chief Li Shangfu.