Russia is holding naval and surface-to-air missile drills in the Black Sea region amid tensions with Ukraine and the West over the capture of three Ukrainian naval ships and their crews off the coast of Crimea last month.
Two submarines, the Rostov-on-Don B-237 and the Stary Oskol B-262, practiced emergency deployments for detecting, accompanying and destroying sea and coastal targets with rocket fire, the Defence Ministry said.
Submarine crews from the Black sea fleet were also due to practice deep dives and to work on techniques such as emergency surfacing, it said.
The statement did not give a start or end date for the drills or say if the submarine exercises were part of larger-scale drills in the Black Sea and on the Crimean peninsula annexed by Russia in 2014.
A navigation warning to shipping published by littoral state Turkey's navy said that "firing exercises" were expected in the region from Dec. 3 to Dec. 9.
Separately, Pantsir medium-range surface-to-air missile systems in the east of Crimea practiced detecting, identifying and shooting down aerial targets, Interfax news agency cited a spokesman for the Black Sea Fleet as saying.
The exercises come at a time of heightened tensions between Russia and the West over Russia's seizure on Nov. 25 of two small Ukrainian armored artillery vessels and a tug boat and their crews.
NATO foreign ministers discussed the Black Sea region with Ukraine and Georgia's foreign ministers on Tuesday while NATO Secretary General Jens Stoltenberg said the U.S.-led military alliance had boosted its presence there in response to what he said were Russia's aggressive actions.