A veteran Maldivian diver alleges the five Italians who died trapped in a deep underwater cave didn’t have the required government authorization to undertake such a perilous dive, and would still be alive today if the rules had been followed.

A group of five Italian scuba divers died exploring the Alimathaa cave in the Vaavu Atoll Thursday, at a depth of about 160 feet, according to Italy’s Foreign Ministry.

Shafraz Naeem, a instructor-trainer with 30 years of technical diving experience and advisor to the Maldives National Defence Force, has done more than 50 dives in the cave where the group disappeared and even a Coast Guard diver died Saturday.

“Everyone knows the rules were broken,” Naeem said in an interview Saturday with Italian news service ANSA.

The entrance to the cave is between 180 and 190 feet deep, and it extends some 330 feet inward, before branching off into narrow tunnels that continue ever deeper, like a descent into the abyss, he noted.

The maximum allowed diving depth in the Maldives is 100 feet for a recreational dive, which is what the ship, the Duke of York — a foreign-operated live-aboard yacht that had another 20 tourists on board and is listed as a PADI Five Star Dive Resort — offers.

The vessel had its license suspended by the Maldives’ Ministry of Tourism Friday as local police and Italian prosecutors investigate the circumstances of the disappearance.

Maldives officials haven’t explicitly said the ship operator didn’t have the required authorization to go below 100 feet, but there is no public evidence that it did.

Both the Italian tour company, Albatros, that runs the boat, and the University of Genoa, that sent the researchers on scientific mission to the Maldives, said they had not authorized the dive.

Naeem said the five Italians likely died from a mix of factors that could include lack of gas reserves, nitrogen narcosis and loss of visibility – adding that in the cave any issue triggers a domino effect.

“Caves are unforgiving because you cannot make a direct ascent,” he said. “Even the most experienced divers can face considerable challenges.”

Only one body, that of diving instructor Gianluca Benedetti, 44, has been recovered so far.

A group of eight divers from the Maldives Coast Guard failed to recover any remains Saturday, and one of them died of suspected decompression sickness in the efforts. A specialized team from Finland is en route to take over the operation.

Monica Montefalcone, 51, a marine biologist from the University of Genoa on a mission to the Maldives to monitor the effects of climate change on tropical biodiversity, also failed to resurface from the dive.

Her daughter, Giorgia Sommacal, 22, and University of Genoa research fellow Muriel Oddenino, 31, were with her.

The other victim was Frederico Gualtieri, 31, a marine biology master’s graduate from the university, who wrote his thesis on coral diversity in the Maldives.