LAST UPDATE | 7 hrs ago

AUTHORITIES IN ESTONIA and Finland are investigating the failure of an undersea electricity transmission cable

EstLink 2 failed suddenly at around 12pm local time on Christmas Day, although there was no interruption of supply between the two countries.

The cable is 170km long, 145km of which lies under the Baltic Sea.

It comes amid increased tensions over the security of undersea infrastructure. In 2022, two still-unexplained explosions damaged the Nord Stream 2 gas pipeline in an incident labelled as ‘sabotage’ by the European Union.

And this month, a Chinese ship has been linked with the cutting of two fibre optic cables in the Baltic Sea. Sweden has accused Chinese authorities of denying prosecutors access to the ship.

Electricity grid operator Fingrid’s operation manager told the Helsingin Sanomat newspaper that sabotage of had not been ruled out, and that two ships were in the area when the fault occurred. However, it was also assessing whether a substation may have failed.

Local police are investigating the incident.

Robin Lardot of Finland’s National Bureau of Investigation said a probe for “aggravated sabotage” had been opened into the oil tanker Eagle S, that flies under the flag of the Cook Islands in the South Pacific.

“The assumption at the moment is that it is a shadow fleet vessel and the cargo was unleaded petrol loaded in a Russian port,” said Sami Rakshit from Director General of Finnish Customs.

The shadow fleet refers to the ships which transport embargoed Russian crude and oil products.

“We monitored the situation closely yesterday” with Prime Minister Petteri Orpo, Finnish President Alexander Stubb on X. “The risks posed by the Russian shadow fleet must be ruled out.”

The Eagle S is bound for Port Said in Egypt and still located in the Gulf of Finland, according to the Marine Traffic website.

“We have already boarded the vessel, spoken with the crew and gathered evidence,” said Lardot.

Police suspect that the oil tanker’s anchor might have damaged the power cable.

“Our patrol vessel travelled to the area and could determine visually that the vessel’s anchor was missing,” Markku Hassinen of the Finnish Border Guard told a news conference.

Engineers from the Finnish and Estonian power grid companies have located the damaged part of the cable.

“The electricity transmission link is out of service for the time being,” Fingrid said in a statement. “The repair of the connection will start as soon as the fault location has been identified.

“The failure of the cross-border electricity transmission link did not endanger the operation of the electricity system in Finland, the electricity system is functioning normally and electricity reliability is currently good.”

Kaja Kallas, the EU’s foreign affairs commissioner, has commended Finnish authorities for their swift response and accused Russia of being behind the incident. She said any instances intentional disruption to undersea cables will be met with sanctions.