Sweden's military says it carried out a second submarine search just a week after calling off a major hunt for a suspected underwater intruder in the Stockholm archipelago in October.

Military spokesman Jesper Tengroth on Sunday confirmed a report in Swedish newspaper Dagens Nyheter that the Navy searched waters near the capital on Oct. 31 after receiving a tip from a "trustworthy" person. No submarine was found.

A week earlier, Sweden had carried out its biggest anti-submarine operation since the end of the Cold War. Swedish authorities later said there was evidence that a small submarine illegally entered Swedish waters before escaping into the Baltic Sea.

It didn't name which country was behind the intrusion. Swedish defense experts said the most likely culprit was Russia.