MOSCOW (AFP) - The Kremlin on Wednesday (July 3) said that details of a fire that killed 14 crew on a deep-water submersible will not be made public because they include classified information.
The seamen died on Monday in Russia's territorial waters in the country's far-north, but the disaster was only made public on Tuesday.
Officials have given little information about the vessel or the circumstances of the accident, with local media reporting that the ship was a secretive nuclear-powered mini-submarine.
"This information cannot be made public completely," Kremlin spokesman Dmitry Peskov said of the disaster. "It belongs to the category of state secrets."
Mr Peskov said that President Vladimir Putin was informed immediately after the fire.
"It is completely normal when this kind of information is not made public," Mr Peskov said, adding that this was "within the law of the Russian Federation".
He said that "no decision has been made" about a period of mourning in the northern Russian region.
The Defence Ministry said the 14 crew were killed by inhaling poisonous fumes after a fire broke out on a "scientific research deep-sea submersible" studying the sea floor.
However, the Novaya Gazeta newspaper cited sources as saying that the accident took place on an AS-12 nuclear mini-submarine, which is capable of going to extreme depths.
The presence of many senior ranking officers on board could suggest that the submarine was not on an ordinary assignment.
President Putin has ordered a full investigation into what he called a tragedy.
He appointed Defence Minister Sergei Shoigu to travel to Severomorsk, the restricted-access military port in the Russian Arctic, and direct the probe.
The incident is the latest in a string of disasters and accidents to hit Russia's navy, with echoes of the sinking of the Kursk submarine in 2000 that claimed the lives of 118 personnel and shook the first years of Mr Putin's presidency.
During a meeting with Mr Shoigu on Tuesday, Mr Putin said the submarine in question was "not an ordinary vessel".
"As we know, it's a scientific-research vessel, its crew is highly professional," the Russian leader said.
He said the victims included seven Captain First Rank officers - the most senior staff officers in the Russian navy - and two have been awarded the Hero of Russia, a top title given out by the president.
A military expert who spoke to AFP on condition of anonymity rubbished claims that the fire happened during scientific research.
"Usually it's a cover for different type of work conducted on the seabed", such as laying cables, the expert said.
The fire was put out and the vessel returned to a military base in Severomorsk. It is not known how many were on board the sub.