Australian doctor and expert diver Richard Harris emerged from a cave in Thailand on Tuesday night knowing all 12 boys and their soccer coach had been saved, only to learn his own father had died.

Dr Harris was hailed a hero, having made the dangerous, four-kilometre journey in and out of Tham Luang cave every day to check on the health of the trapped boys.

Dr Andrew Pearce from South Australia's Ambulance Service’s medical retrieval service confirmed the news of Dr Harris' father's death, saying it had been a "tumultuous week with highs and lows".

"It is with great sadness that I confirm that Harry's dad passed away last night a short time after the successful rescue operation in Thailand," he said in a statement.