Whenever the police makes a raid or seize something for the purpose of investigation it is called in general terms,seizure of property. It could be drugs, it could be anything taken at home or airport etc. If it was to be taken to court specifically it may be called seizure of evidence from a crime scene. Here I don\t think this was the situation.
So seizure of property is the accurate term for this, here I suggest..........those kind of things in the seized property... or in the seizure of property (general terms)