Completely justified--no questions.
I still have questions. As Gabu said, did they identify as police, as required by protocol?
Didn't you know? A very recent Supreme Court (I forget which, I will look it up) ruling stated that police no longer have to identify themselves before they take (lethal) action. But that may be only when entering a house.
EDIT: I was mistaken. The police are allowed to take evidence seized from homes without prior announcement, according to this badly-written
Boston Globe article.