Finnish authorities detained a ship linked to neighboring Russia as they investigate whether it damaged a Baltic Sea power cable and several data cables, police said, in the latest incident involving disruption of key infrastructure.

Finnish police are investigating whether a Russian ship was involved in the sabotage of an electricity cable running between Finland and Estonia. The authorities said on Thursday that they believe the anchor of the Eagle S, a tanker registered with the Cook Islands, may have damaged the Estlink 2 cable, which became disconnected on Wednesday.

Damage to the power cable in the Baltic Sea is the latest in a spate of murky disruptions to undersea cables that have put European authorities on high alert.

Russia’s top security agency says that it has arrested several suspects accused of involvement in an alleged Ukrainian plot to assassinate senior military officers

The Federal Security Service of Russia said a series of assassination attempts had been foiled. Four Russian citizens have been arrested.