Russia's Defense Ministry says a fire on one of its deep-sea research submersibles has killed 14 crew members, RFE/RL reports.

The ministry said on Tuesday, July 2 that the tragedy took place the previous day as the vessel was carrying out a survey in Russian territorial waters.

A Defense Ministry statement said that the sailors died as a result of inhaling combustible fumes aboard the research vessel, which was conducting biometric measurements on the floor of the ocean.

The submersible is now at a navy base in the northwestern city of Severomorsk near Murmansk on the Barents Sea, officials said.

An investigation has been launched.

In 2000, all 118 crew members aboard the Kursk, a Russian nuclear-powered submarine, were killed when the vessel sank to the floor of the Barents Sea following two explosions in a tragedy that gripped the nation at the time.