NATO is ratcheting up its guard against suspected attempts to sabotage underwater energy and data cables and pipelines that crisscross the Baltic Sea.

Nato countries have stepped up patrols to protect critical underwater infrastructure in the Baltic Sea, which is bordered by eight countries, and other waters. A Royal Navy submarine was ordered to surface last November close to a suspected Russian spy ship which was loitering over undersea infrastructure in UK waters.

After a series of suspected undersea cable cuttings, NATO has launched a new surveillance and deterrence mission to protect critical infrastructure under the Baltic Sea.

Sweden is investigating damage to a data cable linked to Latvia, the latest breach in the Baltic Sea region where European authorities are on high alert.

With its powerful camera, the French Navy surveillance plane scouring the Baltic Sea zoomed in on a cargo ship plowing the waters below — closer, closer and closer still until the camera operator could make out details on the vessel's front deck and smoke pouring from its chimney.