Investigation launched into cause of blaze aboard Russian submersible that killed 14 sailors, defence ministry says.

Fourteen Russian sailors on board a submersible military vessel were killed after a fire broke out and they suffocated on the fumes.

The deep-sea research vessel was carrying out a survey in Russia’s territorial waters when the blaze erupted on Monday, the defence ministry said.

President Vladimir Putin on Tuesday called the loss of 14 navy officers in the fire a “big loss”, ordering a full investigation into what happened.

“We express our deepest condolences to the families of those who died. We will do everything we can to support them,” said Putin, who cancelled a public engagement to deal with the incident.

The fire was later extinguished and the submersible subsequently docked at the Northern Fleet’s base in northwestern Severomorsk on the Barents Sea. An investigation was launched to establish the cause of the blaze.

“Fire broke out on board a deep-water scientific research vessel that was studying the marine environment of the world ocean on behalf of the Russian navy,” Interfax news agency cited a ministry statement as saying. “Fourteen submariners died as the result of smoke inhalation.”

‘Spy submarine’?

The report came after Russian news outlet RBC cited an unnamed military source as saying the vessel was a nuclear-powered AS-12 submarine, but there was no official confirmation.

The statement did not identify the type or model of the vessel.

Norwegian authorities said on Tuesday they didn’t detect abnormally high levels of radiation after the incident.

“We have made checks and we are not monitoring too high radiation levels in the area,” Per Strand, a director at the Norwegian Radiation and Nuclear Safety Authority, told Reuters news agency.

He said Russian officials told his agency a gas explosion took place on board the submarine.

Al Jazeera’s Step Vaessen, reporting from the Russian capital Moscow, said the AS-12 was known in the West as a “spy submarine”.

“It is not exactly clear what exactly this vessel can do, but there has been a lot of concern, especially in the United States, that in the case of a global conflict this submarine could cut off all the major internet data and other important data that are used by governments and other important institutions,” she said.

The deadly incident echoes one in August 2000 when a Russian nuclear-powered submarine Kursk sank to the floor of Barents Sea after two explosions in its bow, killing all 118 sailors on board.