An Irish Navy surveillance operation was sparked this week following the appearance of FOUR Russian ships in Irish waters.
Two of the vessels were identified as a merchant ship, The Kama - and a military ship, the Admiral Grigorovich.
The others remain unidentified.
All four were monitored by air and sea patrols, but have now left Irish waters.
The event is the latest in a series of Russian sightings in Irish waters in recent months.
It comes as Europe remains on high alert for possible attacks by Russian military on subsea cables situated off the Irish coastline.