Investigators probing the deadly cave diving tragedy that left five people dead are now examining a dramatic new twist that could reshape the understanding of what went wrong deep underground.

Officials say the five experienced divers died during an unauthorized deep dive inside the Thinwana Kandu cave system in the Maldives’ Vaavu Atoll on Thursday, in what is being described as the country’s worst diving disaster on record.

The victims were identified as University of Genoa ecology professor Monica Montefalcone, her 22-year-old daughter Giorgia Sommacal, marine biologist Federico Gualtieri, researcher Muriel Oddenino, and diving instructor Gianluca Benedetti.

The bodies of four divers were recovered Monday by elite Finnish rescue divers from deep inside the cave’s third chamber, days after the search effort was suspended following the death of Maldivian National Defense Force diver Mohamed Mahudhee, who suffered fatal decompression sickness during the operation.

“As was previously thought, the four bodies were found inside the cave, not only inside the cave but well inside the cave into the third segment of the cave, which is the largest part,” Maldives government spokesperson Ahmed Shaam said, adding the victims were found “pretty much together”.

Benedetti’s body, however, was recovered separately near the entrance of the so-called Shark Cave at a depth of around 197 feet, Italy’s foreign ministry revealed on Monday in a shocking twist in the case.

The Italian tour operator behind the trip has denied approving the dive.

Lawyer Orietta Stella told Corriere della Sera the company “did not know” the group planned to descend beyond 30 meters, adding it “would have never allowed it.”

She also said the divers appeared to be using standard recreational equipment rather than specialized technical gear typically required for deep cave dives.

Despite the controversy, Montefalcone’s husband Carlo Sommacal defended Benedetti, describing him as a “meticulous” instructor.

“He checked everything: the tanks, the weather conditions. He’s not a fool,” he told La Repubblica, adding: “It must have been fate; they took every precaution possible.”

He also said his wife was “among the best divers on earth” and insisted she would never knowingly place the group at risk.

“She would never have put our daughter’s life or that of others at risk… something must have happened down there,” he said.

“Maybe one of them had trouble, maybe the oxygen tanks, I have no idea.”