MADRID » The search for free-diving great Natalia Molchanova was set to resume Wednesday with little hope remaining she would be found alive more than two days after disappearing off Spain’s Balearic islands.

AIDA, the international diving federation, said in a statement that Molchanova had been diving without fins at a depth of 98-130 feet off the coast of Formentera island when she failed to resurface on Sunday.

Maritime rescue coordinator Miguel Chicon said the operation was "very complicated" because the 53-year-old Russian could have become trapped by weights she was wearing at the time of the dive. A submersible robot was brought in to expand the search on Tuesday.

Molchanova was among the most decorated competitors in free-diving, a sport in which participants swim as deeply as they can while holding their breath.