The crew of an oil tanker accused of sabotaging undersea power and communications cables in the Baltic Sea was poised to cut other cables and pipelines when Finnish authorities boarded the vessel last month, the head of the Finnish investigation said.

Baltic Sea nations are on high alert after a string of power cable, telecom link and gas pipeline outages since Russia invaded Ukraine in 2022. Leaders of the NATO member states around the Baltic Sea are set to meet in Helsinki on Tuesday to discuss the alliance's response to the threat.

On Dec. 26, Finnish authorities seized oil tanker Eagle S carrying Russian oil. They said they suspected the vessel had damaged the Finnish-Estonian Estlink 2 power line and four telecoms cables by dragging its anchor across the seabed for more than 100 kilometers.