HELSINKI (Reuters) -The captain and two officers of an oil tanker accused of severing five undersea power and telecoms cables when their vessel left Russia and sailed through the Gulf of Finland in late 2024 will stand trial in Helsinki on Monday.

Investigators have concluded that the Eagle S dragged its anchor along the seabed, severing the Estlink 2 power cable connecting Finland and Estonia, and four internet lines, leading Finnish security forces to interrupt the vessel's journey and board it from helicopters after ordering it to move into Finnish territorial waters.

The three defendants have denied all charges, and the captain told Finnish public broadcaster YLE the incident was "a marine accident".

NATO allies around the Baltic Sea went on high alert following the incident, one of a string of suspicious cable and gas pipeline outages in the region since Russia invaded Ukraine in February 2022.

Finnish prosecutors this month charged the Cook Islands-registered tanker's Georgian captain and Indian first and second officers with aggravated criminal mischief and aggravated interference with telecommunications.

The maximum sentence for aggravated criminal mischief is 10 years in prison, while aggravated interference with telecommunications carries a term of up to five years.

Prosecutors say the damage caused serious risks to energy supply and telecommunications in Finland, and that repair costs total at least 60 million euros ($70 million).

The defendants argue that Finland lacks jurisdiction in the case as the cables were damaged outside Finnish territorial waters, and the court has said it will also consider this claim.

Finnish authorities detained the Eagle S after the cables were severed and released it again in March, while upholding a travel ban on the three now facing trial.

A lawyer for United Arab Emirates-based Caravella LLC FZ, the owner of the Eagle S, has also said Helsinki lacks jurisdiction to intervene in the case.

Last week, a Ukrainian was arrested over the 2022 attacks on the Nord Stream gas pipelines in the Baltic Sea. Both Moscow and the West have described the explosions, which largely severed Russian gas supplies to Europe, as sabotage.

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