Swedes will defend territorial integrity with all available means

Sweden has proof that a small foreign submarine illegally operated in its territorial waters last month, its senior military officer said today after a mysterious episode that triggered the largest mobilization in the country since the Cold War, reports the Bosnian news agency Patria. 

More than 200 soldiers, stealth ships and helicopters searched the Baltic waters off the capital Stockholm in October following reports of foreign "underwater activities", but did not find or bring any submarine to the surface.

"The military can confirm that a small submarine violated Swedish territorial waters. We can rule out all alternative explanations," said the commander of the Swedish Armed Forces, General Sverker Goransson, at a press conference. 

He said that Sweden had failed to identify which country was behind the incursions recorded by military sensors. Supporting evidence, he said, includes an image showing a bubble pattern typical of a diving submarine and a sonar image of traces on the seabed.

Prime Minister Stefan Lofven said that the incursion into Swedish territorial waters was unacceptable and that Sweden would strengthen its capabilities in detecting and identifying such activities.

"We will defend Swedish territorial integrity with all available means," Lofven said.