"Seven members of the Eagle S crew have the status of suspect in this criminal investigation and have been served with a travel ban," Finnish police said in a statement, referring to the oil tanker being held in Finnish waters in the Baltic Sea pending the investigation.
On Christmas Day, the Estlink 2 submarine cable that carries electricity from Finland to Estonia was suddenly disconnected from the grid, just over a month after two telecommunications cables were severed in Swedish territorial waters in the Baltic.
Finnish authorities have been investigating the Eagle S oil tanker that sailed from a Russian port over suspected "sabotage" after it was found nearby missing its anchor.
Investigators said Sunday they found a track on the seabed dozens in kilometres in length but have yet to find the anchor.
The Cook Islands-flagged Eagle S oil tanker
is currently in Porvoo, a town some 40 kilometres (25 miles) east of Helsinki, in the south of the Nordic nation.
