Finnish police have seized a ship suspected of damaging undersea telecommunications cables running from Helsinki across the Gulf of Finland to Estonia.

The cargo ship named “Fitburg”, flying the flag of St. Vincent and the Grenadines, sailed from St. Petersburg to the Israeli port of Haifa.

All 14 crew members were arrested after cables owned by Finnish telecommunications operator Elisa were damaged. The operator said in a statement that the damage “did not affect the functionality of the Elisa service in any way” and that its services had been rerouted.

Police said they were investigating “significant telecommunications disruption” and “serious damage and attempted serious damage”.

The detained crew members include Russians, Georgians, Kazakhs and Azerbaijanis, police added.

Undersea cables carry vital power and data between countries and keep people connected to the internet. In recent years, there have been a series of incidents in the Baltic Sea where underwater cables were damaged or completely severed.

Finnish authorities sent a helicopter and a patrol boat to the area on Wednesday morning and found the ship dragging anchor in the sea, the Finnish Coast Guard said.

They said they “launched operations this morning to investigate suspected cable damage” after telecoms provider Elisa discovered the fault.

Finnish police said authorities “took control of the vessel as part of a joint operation”.

Police added: “At this stage, police are investigating the incident for aggravated criminal damage, attempted aggravated criminal damage and aggravated telecommunications interference.”

Finnish President Alexander Stubb said in a statement on social media: “Finland is ready to deal with various security challenges and we will respond as needed.”

At a press conference, reporters asked police if the cables had been damaged on behalf of another country, local media reported.

Police Chief Ilkka Koskimäki replied “There is no speculation about these matters by the police or other authorities. The police’s job is to investigate what happened.”

Eight NATO countries border the Baltic Sea – Finland, Estonia, Denmark, Germany, Latvia, Lithuania, Poland and Sweden – and also share a border with Russia.

A second telecommunications cable connecting Estonia to Finland also failed on Wednesday, the Estonian government said. The country’s president, Aral Khalis, said “we hope this was not intentional, but the investigation will clarify.”

EU Technical Commissioner Henna Virkkunen posted on X that the European Commission was paying close attention to the incident, adding that it was prepared to deal with “hybrid threats.”

Many experts and political leaders view the recent alleged cable sabotage as part of Russia’s “hybrid war” against the West. The issue has received increasing attention since Russia invaded Ukraine in 2022.

“We are already talking about national security. Critical infrastructure is the frontline,” Finnish MP Jarno Limnell commented on the incident in a post on X.