Finnish rescue divers have shared a new theory about why five Italian divers died while exploring deep-sea caves in the Maldives.

Authorities announced the recovery of the final two bodies from the group on Wednesday, a week after the scuba diving accident thought to be the deadliest of its kind in Maldives’ history.

The divers had been exploring the cave in Vaavu Atoll last Thursday when they disappeared.

The body of their diving instructor was later recovered outside the cave, and the Finnish recovery divers brought two other bodies to the surface Tuesday after they were found in a cave 60m deep.

Professional divers working for medical research organisation Dan Europe found the Italians in a corridor with a dead end inside the cave complex, according to La Repubblica.

CEO Laura Marroni told the outlet she believed the divers may have accidentally taken a turn down the wrong passage as they were trying to exit the caves, from which there “was no way out.”

The cave near Alimatha can be reached by diving 50m, at which point a large bright cavern opens up, Ms Marroni explained.

But the 30m corridor that connects the cavern to a dark second chamber has very little light.

In order to exit the second chamber and make it back to the surface you must rejoin via the corridor, but the conditions can make it confusing for divers, Ms Marroni said.

In particular, a rising sand bank at one end of the second chamber can look like a wall, potentially sending divers on the wrong path to a dead end instead of the exit.

The divers were said to be using tanks that held approximately 12 litres, which would have given them just 10 minutes to visit the second cave, Ms Marroni estimated.

If they had gone down the wrong corridor, she hypothesised, they would have had even less time to escape as panic would have reduced their oxygen supply further.

“Realizing that the path is the wrong one and having little air, perhaps after going back and forth, is terrifying. Then you breathe quickly and the air supply decreases,” she said.

The Italian diving group was ⁠led by Monica Montefalcone, 51, a University of Genoa professor and marine ecologist who was a regular diver in Maldivian waters in the Indian Ocean.

The group included her daughter Giorgia, biomedical engineering student Muriel Oddenino, research fellow Federico Gualtieri, and diving instructor Gianluca Benedetti.

The cave has been explored in the past by local experts and foreign divers, presidential spokesperson Shareef said on Wednesday, but the conditions were known to be "challenging" with difficult terrain, strong currents and poor visibility.

Other experts have mooted different theories, including that the group could have been sucked into the cave where they ran out of oxygen. Maldivian authorities are still investigating.