An undersea fiber optic cable between Latvia and Sweden was damaged on Sunday, likely as a result of external influence, Latvia said, triggering an investigation by local and NATO maritime forces in the Baltic Sea.

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.

BREAKING - Latvia is investigating "significant" damage to an undersea fibre optic cable linking the country with the Swedish island of Gotland, following what officials believe was external interference.

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.

NATO countries will deploy frigates, patrol aircraft and naval drones in the Baltic Sea to help protect critical infrastructure and reserve the right to take action against ships suspected of posing a security threat,

The apparent attack comes less than a month after Nato launched a new mission in the Baltic Sea in response to repeated attacks on underwater power and telecom cables – some of which have been blamed on Russia.

A subsea data cable between Latvia and Sweden was damaged early Sunday, sparking a criminal investigation, a third such incident in the Baltic Sea in the past three months.

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