Two servicemen of the National Guard of the Russian Federation (Rosgvardia) died from injuries sustained during an exercise in Kola Bay, Murmansk.
It is unclear when the accident during a fast-roping exercise from a helicopter onto a ship took place.
Russian media reports said the preliminary results of the investigation indicate that the ropes the two servicemen were using to descend onto the ship had been too short.
It has been said that they fell from a Mi-8 helicopter from a height of 15 meters. Video footage of the accident shows that the weather conditions had also been very poor.
In a unrelated accident on May 21, the crew of an SU-30SM fighter jet ejected from the aircraft as they were preparing for takeoff from the Saki airfield in Crimea.
Both pilots survived the accident, which appears to have been accidental.
In March this year, three crew members of a Russian Air Force Tu-22M3 long-range bomber died in a similar ejection system accident at an airfield near Kaluga. According to the defense ministry, the ejection system was suddenly activated immediately after the engines started on the ground.
According to a TASS report, the Su-30SM fighter that was involved in the ejection accident on Friday is one 104 airframes delivered to the Russian armed forces from 2012 to 2018. It is labeled as 4++ generation multi-role twin-engine fighter jet capable of performing counter-air, counter-land and counter-sea missions.