14 Russian sailors dead in deep sea submersible

The Russian MoD released an announcement

At least 14 Russian Navy servicemen have died after a scientific deep submersible caught fire while on a mission, Russia’s Defense Ministry has said. The cause of the incident is still unknown.
A deep research vehicle belonging to the Russian Navy was conducting a bathymetric measurement operation in the Russian territorial waters when a fire broke out on board, the ministry’s statement says.

The incident claimed the lives of 14 seamen, who were suffocated by smoke. Despite this, the crew managed to extinguish the flames.