Sweden Versus Suspected But Unknown Submarine

It's a story too good for a retired Surface Warfare/Inshore Undersea Warfare guy to resist - the Swedes once again looking for a suspected submarine in their waters as Russia denies involvement with what may be the classic "who us?" quote of this undersea adventure:

“On Sunday the Russian Defense Ministry provided whatever aid it could to the Swedes in their futile search,” a Russian Ministry of Defense source told the state controlled Russia Today on Monday. (Hat tip to Sam LaGrone at USNI News)

And the Russians know this is a"futile search" how?

Well, if it was their boat and it has escaped from Swedish waters then they know where it isn't - meaning that it's not there for the Swedes to find.

Because if it is -say- a Bolivian submarine operating for some odd reason in the Baltic and in Swedish waters, then the search being conducted by the Swedes might not be so . . . futile, right?

Salamander has thoughts on, among other things, anti-submarine warfare readiness here.

What is the ASW package on those cool looking Visby corvettes?

Small Russian subs? How about Project 1910, Kashalot (picture above)