I don’t know but I can guess - threatening or brandishing. No arrests or charges, just an “investigation”. They will Probably be returned to the owner in a year or so (or their next of kin)
Going to see if he has a legally obtained firearm... You know they have an angle to charge him and make an example of him.
This is a sleight of hand local police do all the time.
Seize your property and declare an investigation. Your property is then declared ‘evidence’ and remains in the evidence locker in perpetuity.
They’ll never get their property back.