The investigation into the deaths of five Italian tourists during a deep cave dive in the Maldives is increasingly focusing on one terrifying possibility: something may have gone catastrophically wrong with the divers’ breathing systems deep underwater.

Authorities in the Maldives have not yet released a final official cause of death. However, diving experts reviewing the circumstances surrounding the tragedy say oxygen toxicity, gas-mixture failure, or panic triggered by equipment complications may explain why all five experienced divers vanished during the same descent into an underwater cave system near Vaavu Atoll.

The case has shocked the global diving community not only because of the number of victims, but because many of those who died were highly educated marine researchers and experienced divers — including university scientists, a diving instructor, and environmental specialists connected to the University of Genoa.

But what continues haunting investigators most is the growing theory that the danger may have begun inside the oxygen tanks themselves.

Divers reportedly descended far beyond recreational safety limits

According to Maldivian authorities and multiple international reports, the group entered an underwater cave system at depths approaching 50 meters (around 160 feet) — significantly deeper than the Maldives’ standard recreational diving limit of approximately 30 meters (100 feet).

Experts say dives at those depths require:

specialized technical training,
carefully calibrated gas mixtures,
decompression planning,
and equipment specifically designed for deep cave environments.

Several diving specialists reviewing the case believe the victims may have used oxygen-enriched gas mixtures that became dangerous at extreme pressure levels underwater.

One pulmonologist interviewed by Italian media reportedly stated that if oxygen concentration inside the tanks was improperly balanced for that depth, the divers could have experienced oxygen toxicity — a condition capable of causing:

confusion,
dizziness,
seizures,
panic,
loss of consciousness,
and drowning within moments underwater.

Experts say the cave itself may have amplified the disaster

The dive reportedly took place inside a complex underwater cave network near Alimathaa in Vaavu Atoll, an area known for strong currents, narrow passages, and dangerous visibility conditions.

Former technical divers say cave systems create one of the deadliest environments possible once panic or disorientation begins.

Unlike open-water diving, caves eliminate direct ascent routes. If even one diver experiences distress inside a confined tunnel, visibility can collapse instantly as sediment fills the water.

That possibility has become central to the investigation because experts remain deeply disturbed by one detail:
all five divers failed to return.

Several analysts now believe a shared equipment or gas-related problem may have triggered simultaneous confusion or incapacitation inside the cave.

Rescue efforts became deadly themselves

The danger surrounding the site became even more horrifying after a Maldivian military diver died during recovery operations days later. Authorities said the rescue diver suffered decompression-related complications while searching the underwater cave system.

The recovery mission was later partially suspended due to:

shark activity,
rough weather,
extreme depth,
and the technical dangers of navigating the cave passages.

Elite Finnish cave divers were eventually brought to the Maldives to remap the underwater cave system and continue searching for the remaining bodies.

The oxygen tank theory continues haunting the diving community

Although investigators continue examining weather conditions, dive planning, permits, and cave navigation, the oxygen-tank hypothesis has become one of the most discussed aspects of the case internationally.

Experts say oxygen toxicity deaths are especially terrifying because victims may become mentally impaired before fully realizing what is happening. Underwater, even seconds of confusion can become fatal.

One diving specialist described the condition as “one of the most dramatic deaths possible underwater.”

For many following the tragedy, the most chilling realization is that the disaster may not have started with rough seas or the cave itself —

but with the invisible gas the divers trusted to keep them alive beneath the Atlantic-blue waters of the Maldives.