Not got much detail on this, but the SCMP’s “In Brief” section has the following:
“Rescuers search for missing diver
A man in his 30s or 40s was reported missing after going diving at Ung Kong Wan in Sai Kung at 3.40pm. Rescuers were continuing to search for him last night. ”
Ung Kong Wan is off Bluff Island where SCDC did a beach clean-up a couple of weeks ago. There doesn’t appear to be any more information in the English language press at the moment.