A serving Navy officer and two retired officers have been arrested by the Central Bureau of Investigation (CBI) for allegedly leaking confidential information on the upgrade of the Navy's Kilo class submarines.
More arrests are likely in the case and it is unclear so far if foreign intelligence agencies were involved in the information leak.
The Navy said in a statement, "Investigation related to alleged information leak of administrative and commercial nature being with some unauthorised personnel has come to light and is being investigated by appropriate government agency. The investigation by the agency with complete support of the Indian Navy is in progress. An internal inquiry by the Navy is also being progressed."
Navy sources have confirmed that the matter is being investigated by a Vice-Admiral and a Rear Admiral.
The Mumbai-based serving officer accused of sharing the classified information holds the rank of Commander.
Kilo class submarines, designed and built in the Soviet Union for the Soviet Navy, are among the world's most common conventional submarines and are currently in service in the navies of several countries.
In India, these submarines are categorised under the Sindhughosh class. Till date, the government has acquired 10 such submarines, all of which have gone through extensive modernisation, some details of which remain classified.
The Navy currently has 15 conventional submarines and two nuclear submarines.