Captain Marko Petkovic said the Russian Navy's submarine presence in the Baltic Sea has reached levels where encounters now occur almost weekly, as Moscow continues to expand and modernize its fleet.Petkovic explained that about one new Kilo-class submarine is produced annually in Saint Petersburg and Kaliningrad, signaling a significant buildup of Russian underwater capabilities.NATO has intensified annual submarine-hunting drills like "Playbook Merlin 25" and launched Operation Baltic Sentry to enhance regional maritime security and protect underwater infrastructure.