NATO said on Friday it would boost its presence in the Baltic Sea after the suspected sabotage this week of an undersea power cable and four internet lines, while alliance member Estonia launched a naval operation to guard a parallel electricity link.

Police and media reports say that Finnish authorities have detained a Russia-linked ship as they investigate whether it damaged a Baltic Sea power cable and several data cables.

In a latest development it has been known that another same kind of an incident took place again at the Baltic Sea where the undersea power cable linking Finland and Estonia has broken down and authorities are not ruling out sabotage.