Finnish police have seized a cargo vessel suspected of damaging an undersea cable.
The Fitburg had departed from Russia and was en route to Israel when Finnish authorities detained the ship.
It is suspected of causing damage to a telecoms cable running from Helsinki to Estonia's capital Tallinn.
"Finnish authorities have taken control of the vessel as part of a joint operation," police said.
Fourteen crew members - said to be Russian, Georgian, Kazakh and Azerbaijani - are being held by authorities.
Eight NATO states border the Baltic Sea, which also borders Russia.
They have been on high alert after a spate of outages of power cables, telecoms links and gas pipelines that run along the relatively shallow seabed since Russia invaded Ukraine in 2022.
NATO has boosted its presence in the Baltic with frigates, aircraft and naval drones in recent years.
A spokesperson for the military alliance declined to comment on Wednesday's incident.
The Fitburg sailed under the flag of St Vincent and the Grenadines, a police spokesperson said.
It had departed from St Petersburg in Russia and was headed to Haifa in Israel, according to MarineTraffic data.
The vessel was dragging its anchor in the sea, and was directed to Finnish territorial waters, the police and Finland's Border Guard stated.
The cable belongs to Finnish telecoms group Elisa.
"At this stage, the police are investigating the incident as aggravated criminal damage, attempted aggravated criminal damage, and aggravated interference with telecommunications," the police said.
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Estonia's justice ministry said a second telecoms cable connecting the country to Finland had also suffered an outage on Wednesday.
It was not immediately clear if the cable, belonging to Sweden's Arelion, was running parallel to Elisa's.
Finland's President Alexander Stubb said the situation was being monitored.
Posting on X, he added: "Finland is prepared for various security challenges and responds to them in the manner the situation requires."
In December last year, Finland boarded the Russian-linked oil tanker Eagle S which investigators said had damaged a power cable and several telecoms links in the Baltic Sea by dragging its anchor.
A Finnish court in October dismissed a criminal case against the Eagle S captain and other crew members, ruling prosecutors failed to prove intent and that any alleged negligence must be pursued by the ship's flag state or the crew's home countries.
(c) Sky News 2025: Finland police seize vessel suspected of damaging Baltic Sea cable
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