Finland said a Russia-linked oil tanker was close to wreaking havoc on its undersea cables.Its president said that officials intervened about 12 minutes before the damage got "much worse."The tanker is accused of being part of a Russian "shadow fleet" sabotaging European infrastructure.Finnish President Alexander Stubb said on Tuesday that his country had stopped the crew of a Russia-linked oil tanker just minutes before it caused catastrophic damage to undersea cables in the Baltic Sea."Had it continued for another 12 minutes, the carnage would have been much worse than the four basic cables that were there," Stubb told reporters at this week's Baltic-focused NATO summit in Helsinki.The tanker, the Eagle S, was seized in late December as Finland probed recent damage to its Estlink-2 power line, one of two vital cables carrying electricity in the Baltic Sea.Four data cables were also severed.Finnish investigators have accused the Eagle S crew of trying to sabotage the cables by dragging the ship's anchor for miles along the seabed.The Finnish head of the investigation, Risto Lohi, told Reuters on Tuesday that the Eagle S would likely also have attempted sabotage on the other power cable, the Estlink-1, had police not boarded the vessel."There would have been an almost immediate danger that other cables or pipes related to our critical underwater infrastructure could have been damaged," said Lohi, who is the chief of Finland's National Bureau of Investigation.On Tuesday, Stubb said that Finland's security process for protecting the cables started with the private company overseeing them. If a cable is severed, the firm would alert the authorities, who then try to find possible ships around the location of the damage."Once that happens, you identify the ship and contact the ship. Number four, you stop the ship," Stubb said.Stubb added that Finnish authorities would compel the ship to enter Finnish waters, where officers could then legally board the vessel.That process is set to change now. European members of NATO announced at the summit that they would launch a new program, called the "Baltic Sentry," to collectively patrol near Baltic Sea infrastructure.The surveillance program involves frigates, maritime aircraft, and "a small fleet of naval drones," said NATO's secretary-general, Mark Rutte, at the summit.The investigation into the Eagle S is of particular significance to the European Union because it's suspected for years that Russia has been intentionally trying tocovertly damage Western undersea infrastructure.Other cables, such as two fiber-optic data cables running between Finland and Germany, were cut last year.Though the Eagle S is registered in the Cook Islands, European officials say it's tied to Russia because it was carrying 35,000 tons of unleaded gasoline loaded in Russian ports.They have accused the ship of being part of a Russian "shadow fleet," or a network of vessels with owners registered outside Russia that are actually carrying sanctioned Russian oil.Russia has denied being involved in any way with such sabotage. The Russian Foreign Ministry did not respond to a comment request sent outside regular business hours by Business Insider.