NATO officials are investigating damage discovered on Sunday to another undersea cable running across the Baltic Sea, this time a telecommunications link between NATO member states Sweden and Latvia.

Sweden has opened a preliminary investigation into suspected aggravated “sabotage” and ordered the detention of a vessel in the Baltic Sea suspected of damaging an underwater fiber optic cable connecting Latvia and the Swedish island of Gotland earlier that day.

An undersea fibre optic cable between Latvia and Sweden has been damaged, likely due to external influence, prompting a joint investigation by NATO and Baltic nations. Swedish and Latvian authorities are cooperating to assess the situation and determine necessary actions for the repair and protection of critical infrastructure.