NATO Secretary-General Mark Rutte said Friday that the military alliance will step up patrols in the Baltic Sea region as Finnish investigators work to establish whether a ship linked to Russia sabotaged undersea cables there this week.

Investigators have discovered anchor drag marks along the seabed allegedly caused by the Russian ship’s antics.

Finland says a ship affiliated with Russia's "shadow fleet" is linked to a 60-mile-long anchor drag mark on the seafloor. A power cable in the Baltic Sea was severed last week.

G rey-zone operations, hybrid warfare, slicing the salami: there are many terms for Russia’s use of covert attacks that leave opponents unsure how to respond. The latest theatre seems to be the Baltic Sea. Twice in the past two months, commercial ships with Russian links have been accused of damaging cables by dragging their anchors.

NATO sources told the Finnish newspaper Iltalehti that Russia will try to create a 'buffer zone' stretching from the Arctic to the Mediterranean Sea.

The vast majority of the world's data runs through undersea cables, which can be exposed to attacks under what is known as hybrid warfare.

The government’s proposal, which has gained the majority support of the main opposition parties in the Eduskunta, the parliament here, would reposition Finland’s annual spending on defense closer to 3.3% of GDP, placing it well above NATO’s 2% guideline.

The damaged cable is one of several recent incidents in the Baltic Sea under investigation as possible acts of sabotage.

Police in Finland probing damage to undersea cables say a shadowy Russia-linked ship may have dragged its anchor for more than 60 miles.

NATO said on Friday it would boost its presence in the Baltic Sea after the suspected sabotage this week of an undersea power cable and four internet lines, while alliance member Estonia launched a naval operation to guard a parallel electricity link.

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 Finnish court on Friday denied a request for the release of an oil tanker suspected by police of damaging an undersea power line and four telecommunications cables in the Baltic Sea last week. Finland on Dec.