Finland seized an oil tanker that authorities believe might have deliberately cut vital undersea cables. Finnish authorities believe the tanker may be linked to Russia.

A vessel delivering oil for Russia was detained by Finland authorities on Thursday in connection with an undersea cable cutting incident that disconnected electricity to Estonia.

It’s the latest in a spate of murky disruptions to undersea cables that have put European authorities on high alert and heightened fears of sabotage by Russia.

Finnish authorities seized the Russian oil tanker Eagle S after the country’s police opened a criminal investigation into the vessel’s possible involvement in another cutting of undersea power and communications cables in the Baltic Sea on Christmas Day,

Police and media reports say that Finnish authorities have detained a Russia-linked ship as they investigate whether it damaged a Baltic Sea power cable and several data cables.

Finland has seized an oil tanker suspected of having severed undersea power and internet cables, with Finnish authorities saying the vessel may have been part of Russia's "shadow fleet" of ships aimed at skirting Western sanctions.

Nato also says it will enhance its military presence in the Baltic after a ship was suspected of sabotaging the Estlink 2 cable.

General Mark Rutte says the military alliance will step up patrols in the Baltic Sea area as Finnish investigators work to establish whether a ship linked to Russia sabotaged undersea cables there this week.

Estonia dispatched a navy ship to patrol a 105-kilometer (65-mile) subsea power link a day after Finland seized an oil tanker suspected of damaging five cables with its anchor.