Indonesian rescuers have been searching for seven Japanese divers missing off the island of Bali since Friday.
The seven, all experienced divers, disappeared in bad weather while exploring an area of mangroves.
The BBC reports conditions were reported to be bad at the time the group disappeared, with heavy winds and strong rains.
The group were diving near the island of Nusa Penida, a small island some 20km off the coast of Bali itself.
They had gone for two diving trips on Friday morning but failed to return after a third trip in the afternoon.
The Japanese Kyodo agency quoted government officials as saying all members of the party had completed at least 50 dive trips previously, while the instructors were based locally and so knew the area.
Nusa Penida, popular with divers because of crystal clear waters and the opportunity to see rare Ocean Sunfish, is known for treacherous currents. A number of fatal accidents have occurred there.