Countries in the Baltic Sea region have been on high alert following a string of incidents which saw undersea power cables, telecoms links and gas pipelines damaged.
A vessel seized in Finland suspected of damaging an undersea telecommunications cable between Helsinki and Tallinn was transporting Russian steel subject to European Union sanctions, Finnish customs officials said on Thursday.
On Wednesday, Finnish police detained the Fitburg, a 132-metre-long cargo ship en route from St Petersburg in Russia to the Israeli port of Haifa.
Its 14 crew members were also detained following suspicion the ship's anchor had damaged the telecoms cable in the Gulf of Finland.
"Preliminary information indicated that the cargo consisted of steel products originating in Russia, which are subject to extensive sanctions imposed on Russia," Finnish Customs said in a statement.
The agency had carried out an inspection of the ship's cargo late on Wednesday.
"According to the assessment of experts at Finnish Customs, the structural steel in question falls under the EU's sectoral sanctions," it said.
"Import of such sanctioned goods into the EU is prohibited under EU sanctions regulations."
Finnish Customs said it was still investigating "the applicability of EU sanctions legislation to this case."
The steel remained impounded pending clarification, it said, and Finnish Customs has opened a preliminary inquiry "with a view to launching a pre-trial investigation into a potential sanctions violation."
Finnish police said on Wednesday they were investigating the damaged cable incident as "aggravated criminal damage, attempted aggravated criminal damage, and aggravated interference with telecommunications."
'Hybrid war'
The Fitburg is flagged from St Vincent and Grenadines and its 14 crew members - from Russia, Georgia, Azerbaijan and Kazakhstan - were detained and are to be questioned by Finnish police.
Two of the crew members were placed under arrest on Thursday and two others were placed under a travel ban, police said, refusing to disclose their nationalities or roles in the crew.
Energy and communications infrastructure, including underwater cables and pipelines, have been damaged in the Baltic Sea in recent years.
Since Russia's full-scale invasion of Ukraine in February 2022, many experts and political leaders have viewed the suspected cable sabotage as part of a "hybrid war" carried out by Russia against Western countries.
EU foreign affairs chief Kaja Kallas said Thursday that Europe "remains vigilant" as its critical infrastructure was "at high risk of sabotage".
"The EU will continue to fortify its critical infrastructure, including by investing in new cables, strengthening surveillance, ensuring more repair capacity, and moving against Moscow's shadow fleet, which also acts as a launchpad for hybrid attacks," she wrote on X.
The cable damaged Wednesday is owned by Finnish telecoms group Elisa and located in Estonia's exclusive economic zone. Elisa said its services were rerouted and the damage did not impact customers.
Similar incidents
In December 2024, Finnish authorities boarded the Russian-linked oil tanker Eagle S which investigators said had damaged a power cables and telecommunications links in the Baltic Sea by dragging its anchor along the seabed.
That case was dismissed by a Finnish court in October after prosecutors failed to prove intent.
There are eight NATO countries bordering the Baltic Sea, which also borders Russia, and they have been on high alert following a string of incidents which saw undersea power cables, telecoms links and gas pipelines damaged.
Those incidents have generally been regarded as deliberate acts of sabotage suspected of being linked to Russia and have prompted NATO to boost its presence in the region with patrol frigates, aircraft and naval drones.