The Kremlin on Wednesday said details of a fire that killed 14 crew aboard a deep-water submarine would not be made public because they include classified information.

"This information cannot be made public completely," Kremlin spokesman Dmitry Peskov said. "It belongs to the category of state secrets."

Peskov also said the decision to not reveal the details is "within the law of the Russian Federation".

A total of 14 seamen died Monday in a fire that broke out on a Russian research submarine in the country's far-north territorial waters.

"On July 1, a fire broke out during biometric measurements on a scientific research deep-sea submersible," Russian's defense ministry confirmed the incident on Tuesday, saying the sailors died of inhaling toxic substance from the fumes.

Following the incident, President Vladimir Putin has ordered an inquiry into it in a meeting with his defense minister Sergei Shoigu.

(Cover image via VCG: Sailors stand in formation next to the monument to the city of Murmansk as they commemorate 14 submariners who died on Monday, July 1, after the fire broke out aboard the Navy research submarine of the Russian Northern Fleet, in Sevastopol, Crimea, Russia.)