The Indian Navy’s new $3 billion fleet of submarines – said to be the quietest in their class – may have been compromised after 22,400 pages of top-secret files detailing the vessels’ stealth capabilities were reportedly leaked from a French shipbuilder.

The leak describes in detail vital features of six Scorpene-class submarines that the French state-owned shipbuilding company DCNS designed for the Indian Navy, according to the Australian – which published a number of redacted documents on its website.

It could become an intelligence gold mine for India’s rivals such as Pakistan or China, given the potential use of the data to detect, identify and destroy the French-built submarines in wartime.

A DCNS spokesperson said the company is unsure if the information is correct, adding: “the competition is more and more hard and all means can be used in this context.”

France wins $39bn contract to build fleet of world’s 'most sophisticated' subs for Australia https://t.co/HglkyD54Unpic.twitter.com/q6xD2dZN3j — RT (@RT_com) April 26, 2016

The leaked DCNS files detail frequencies on which the Indian Scorpene submarines gather intelligence, the levels of noise they make at various speeds, as well as their diving depth, range and endurance. Furthermore, the documents describe where on the boat the crew can speak safely to avoid detection by the enemy.

The leak also discloses the specifications of the Scorpene’s torpedo launch system and weapons control electronics, which would allow an adversary to uncover the strengths and weaknesses of the Indian Navy’s submarine forces.

The data seen by the Australian lists 4,457 pages on the submarines’ underwater sensors, 4,209 pages on their above-water sensors, 4,301 pages on their combat control system, 493 pages on their torpedo launch system, 6,841 pages on the subs’ communications, and 2,138 on their navigation systems.

The $3-billion project – which the Indian government hopes will significantly improve India’s naval power in the region – is already four years behind schedule. The DCNS-designed Scorpene was chosen ahead of its German and Japanese rivals because of its superior stealth capabilities.

Twelve submarines of the same type are currently being built by the French for the Australian Navy, a major US ally in the region. Australian Prime Minister Malcolm Turnbull said the leak was “worrying” and could have a potential impact for the country’s security.

On Tuesday, DCNS implied the leak might have originated in India, where the six Scorpenes are being assembled, insisting that the company does not control the handling of technical data used by a local builder.

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However, according to the Australian’s sources, the leaked files had been written in France in 2011, removed from the country by a former French Navy officer and DCNS subcontractor, and later passed to a Southeast Asian company.

The data was then reportedly sent on a data disk by regular mail to a company in Australia. It is unclear how widely it was shared or whether it was obtained by foreign intelligence agencies.

Other files in the leak seen by the newspaper include separate top-secret DCNS documents on plans to sell French frigates to the Chilean Navy, as well as the canceled deal to deliver Mistral-class amphibious assault ships to Russia. Those documents have no link to India, which adds to the possibility that the data was leaked from France.

"I understand there has been a case of hacking," Indian Defense Minister Manohar Parrikar told reporters on Wednesday, commenting on the scandal. "We will find out what has happened."

Later on Wednesday, DCNS said it will determine whether the leak has affected other company clients. "We're going to determine ... if harm was caused to our clients and establish action plans," a company spokesman said, as cited by Reuters.

An anonymous source close to the matter has also claimed the leak “seems to be sensitive information but appears neither critical nor confidential."

Except India, Scorpene-class submarines are operated by the Malaysian, Spanish and Chilean Navies.