Sweden says it has evidence of intrusion by mini sub in October
Military says it can confirm a boat entered its territory last month but from where is unknown
Sweden claims it has evidence that a mini submarine entered its waters, triggering a week-long hunt with echoes of cold war stand-offs fuelled by speculation of a Russian incursion.
The October search, which stirred up memories of cat-and-mouse games with suspected Soviet submarines along Sweden's long, rugged coastline, involved frigates, minesweepers and helicopters as well as more than 200 troops.
But now the Swedish defence force said it had confirmed that a mini submarine did violate Swedish territory - but said it was impossible to confirm the vessel's nationality.
"This is a serious and unacceptable violation by a foreign power," said the commander of the Swedish armed forces General Sverker Goeranson.
Prime Minister Stefan Loefven issued a warning against any future incursions.
"We will defend our territorial integrity with all available means. The armed forces have the necessary power to prevent a foreign vessel from getting away with it ... and to do so with military force," he said.