MOSCOW (Reuters) – A fire aboard a top-secret Russian nuclear submarine could have led to a “catastrophe of global proportions” if not for the selfless actions of the crew, a senior navy official was cited by a Russian media outlet as saying.

Fourteen submariners were killed on July 1 during a fire in a deep-water research submersible that was surveying the sea floor near the Arctic, according to Russia’s Defence Ministry.

Russian officials have faced accusations of trying to cover up the full details of the incident on the top secret vessel. President Vladimir Putin only acknowledged publicly there had been a nuclear reactor on board three days after it happened.

The sailors were buried on Saturday in St Petersburg at a funeral ceremony that was closed to the public.

“They all shared one and the same fate – to save the lives of their comrades, to save their vessel and to prevent a catastrophe of global proportions at the cost of their own lives,” Sergei Pavlov, an aide to the Russian navy’s commander, was quoted as saying at the funeral by St Petersburg media outlet Fontanka on Saturday.

In the comments from Pavlov quoted in Russian media, there was no explanation of how the fire could have resulted in a global catastrophe. Russian officials have said the crew contained the fire and isolated the submarine’s nuclear reaction.

Kremlin spokesman Dmitry Peskov, told reporters on a conference call he was unaware of the comments made by officials at the funeral and was therefore unable to comment.

Putin last week bestowed Russia’s highest state award – the title of Hero of Russia – on four of the men and granted another top state award — the Order of Courage — to the 10 others.

Putin has said that the submarine was manned by an elite and senior crew, two of whom already held the Hero of Russia title before their final mission.

(Reporting by Tom Balmforth and Andrew Osborn; Writing by Tom Balmforth; Editing by Alison Williams)