Originally Posted by Rob2160

Apparently the police were friendly and did not target that RC field specifically. They heard the report of a drone sighting at 3,100ft over the radio and happened to be flying past the field and noticed one of the pilots on the ground wearing FPV goggles.

This is why they landed but when the Club safety officer assured them it wasn't any of his club members they were happy and left. The Police didn't mention FAA registration at all. ( I got these details second hand but I think that is the gist of it)