This was reported by press-office of Defense Intelligence of Ukraine.
According to Ukraine's Intelligence, a strike naval drone involved in the operation conducted by Ukrainian intelligence officers penetrated the bay of the city of Novorossiysk (Novorossiysk Bay or Tsemess Bay), where the russian side holds part of the Black Sea Fleet's naval fleet.
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After losing contact with the control point, presumably due to the influence of russian electronic warfare equipment, the drone remained in the operation area.

Subsequently, the command of the russian Navy gave the order to raise the Ukrainian drone from the water for the purpose of research. A group of five russian commando frogmen from a special detachment for combating underwater sabotage forces and means (PDSS) was involved to carry out this task. This is a specialized unit of the russian Navy, staffed with highly qualified specialists in intelligence and underwater activities.
During manipulations with the Ukrainian drone, an explosion occurred, as a result of which all five russian commando frogmen died.
The Defense Intelligence of Ukrain of the Ministry of Defense of Ukraine reports that the deceased divers were part of an elite unit, the training of which requires significant resources and time. At the same time, there is growing dissatisfaction among the personnel of the Black Sea Fleet, which is based in Novorossiysk, due to the order that led to the losses.
The Ukrainian side did not provide additional comments on further plans for the operation.

As Defense Express reported, earlier Ukrainian Defense Intelligence drones hit key railway junction in russia's Voronezh region. We also wrote, that Ukrainian Defense Intelligence drone operators showed high effectiveness on the battlefield.
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