This article is more than 1 year old

This article is more than 1 year old

Russia has revealed a fire onboard a top-secret navy submersible has left 14 sailors dead in a rare public incident involving one of the country’s most shadowy military projects.

The Russian defence ministry did not identify the submersible by name, simply calling it a “deep-sea research vessel”. Several independent Russian media outlets, including RBC and Novaya Gazeta, identified the vessel as the Losharik, citing sources.

Vladimir Putin, the Russian president, said the crew was “highly professional”, adding that seven of the dead had the rank of captain and two were awarded the nation’s highest medal, the Hero of Russia.

The Losharik spy submarine is believed to be nuclear powered, capable of diving to extreme depths and possibly involved in the tapping and severing of underwater communications cables.

The fire broke out on Monday while the vessel was carrying out research in Russia’s northern territorial waters, the defence ministry said.

The sailors died from inhaling poisonous gas as a result of the fire, the ministry said. Russian officials did not say what caused the blaze, although they did say the vessel was performing bathymetric measurements in a study of the ocean floor.

The submersible is now at the Russian northern fleet’s base in Severomorsk on the Barents Sea.

The Russian president, Vladimir Putin, cancelled a scheduled appearance and summoned his defence minister to be briefed on the situation. He ordered an inquiry into the incident.

In 2000, the Russian nuclear-powered submarine Kursk sank to the floor of the Barents Sea after two explosions in its bow, killing all 118 crewmen. The incident prompted criticism of Putin’s government for not acting quickly enough or accepting international offers of support to save the sailors.

Russia has released little information about the Losharik and photographs of the vessel are also rare. The clearest photograph is believed to have been accidentally published by Top Gear magazine, which inadvertently captured it while covering a test drive of a Mercedes-Benz GL450 in Arkhangelsk, northern Russia.

Vessels with deep-sea diving capabilities such as the Losharik are believed to be capable of “seabed warfare”, threatening underwater power and communications cables, as well as carrying out topographical research and performing rescue missions.

In a report on Russian naval capabilities, researchers at the Washington-based Center for Strategic and International Studies said such vessels “could be used to either tap or outright sever vital communications linkages either in the Baltic Sea or north Atlantic”.

It is also believed the Losharik may be carried by a retrofitted ballistic missile submarine that can act as a “mothership” for minisubs and other small vessels.