Russian government vessels equipped with technology capable of interfering with subsea cables have returned to the west coast after appearing to depart towards Africa earlier in the week.
The two Russian flagged ships, the Umka and the Bakhtemir, caused alarm among defence officials late last week when they were spotted engaging in unusual manoeuvrers off the Galway coast, in the vicinity of a newly opened subsea communications cable.
The Defence Forces deployed ships and aircraft to keep track of the vessels, which later turned south and appeared to resume their originally charted journey to the port of Malabo in Equatorial Guinea on the west coast of Africa.
Following analysis, Defence Forces officials determined the ships were likely trying to avoid bad weather by doubling back.
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However, on Thursday night just before leaving the Irish Exclusive Economic Zone (EEZ), the ships turned around again and began sailing back up the west coast, causing further confusion about their intentions.
The latest available position from marine tracking software places the ships about 100km west of the Dingle Peninsula in Kerry. Air Corps and Naval Service personnel are continuing surveillance but have declined to release further details.
Work was continuing on Friday to determine the ships intentions and whether they are simply continuing to shelter from storms in the North Atlantic. These efforts, however, were stymied by the fact that as of Friday afternoon the Naval Service had no ships at sea due to a lack of personnel.
Both ships had been involved in the construction of the Nord Stream 2 pipeline, resulting in them being sanctioned by the US government.
EU countries, including Ireland, have stepped up surveillance of vital subsea infrastructure since the explosions that disabled the Nord Stream pipelines last year. The culprits have not been identified, although the US, Russia and Ukrainian groups have all been accused of being behind the attack.
The Umka is an offshore supply vessel that is believed to be towing a cable-laying barge. The Bakhtemir is classified as a salvage and rescue ship equipped with diving platforms and high-tech submersibles capable of deep water work on infrastructure.
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Both are operated by the Russian Marine Rescue Services, which was also sanctioned by the US for its involvement in Nord Stream 2.
On Thursday Yuriy Filatov, Russia’s ambassador to Ireland, criticised reporting of the presence of Russian ships off the west coast.
“The purpose of this story seems to be to once again create an impression of ‘suspicious’ Russian maritime activity, allegedly aimed at sabotaging subsea communication cables.”
He said the real threat to international maritime infrastructure lies elsewhere and said there are “serious grounds” to believe the US was behind the Nord Stream explosions.