The Russian-built submarine has mostly sunk from the damage , the defense ministry said , and only a part of it is visible . Russia : The defense minister confirms some deaths but does n't say how many . About 18 people were reportedly on board when the blast happened . Rescue efforts are still under way . The Russian - built submarine has mostly sunk following the explosion and fire .
Russia : The defense minister confirms some deaths but does n't say how many . About 18 people were reportedly on board when the blast happened . Rescue efforts are still under way . The Russian - built submarine has mostly sunk following the explosion and fire .