http://theaviationist.com/2014/08/01...dish-airspace/
There have been many cases of airspace violations in the region during the last few years. Pure speculation but if a state operated stealthy drone was transiting the area it's doubtful it would be talking to anyone other than the operator.
Lets hope this is not the case.
"That region" = over sea east of Sweden. But this was not "that region". It was border-close between Norway and Sweden. Good surveillance, both technical equipment and the will to keep control in the area.
Sweden only fly UAV in active restriction areas in Sweden. Highly regulated and taken very seriously by Swedish armed forces.
As for the radar picture linked in my last reply: In my eyes it sure looks like a raw/primary radar trace. I would guess on a military surveillance radar with both primary and secondary targets shown. For reference, the length of the trace is aprox. 1 minute of flight on the picture but it shows (guesstimated) about 100 radar position dots. The SSR-system, I think, don't produce close to that number of measurements in one minute.
But then, Im not in that bussiness, so I might be wrong about that.