It's difficult to say for sure what happened without more information. It's possible that someone saw the package at my door and reported it to the authorities. But how know it's SN? Could also be that the police may have obtained info with a warrant.
We don't have all the information needed to make a definitive conclusion about what happened. Need be cautious about jumping to conclusions. Only time will tell.
It's difficult to know for sure what happened and why. But most importantly, be careful who you share sources with, as others have said, there is a high probability SN will fall much like N did.
No search warrant, whole encounter lasted maybe 5 minutes. It's taken me a few hours to calm down.