Is it a felony to own a double edged blade/knife in Mass?

A search warrant for marijuana and anything pertaining to the sale and distribution of marijuana was issued on a home. Within the home, in a bureau drawer they found a sword collection. Among the swords were two double edged swords. The swords were taken by the detectives and the subject of the search warrant was informed that owning any double edged blade was a felony in Mass. He is allegedly going to be charged with this felony and summons to court. I've researched Mass laws regarding knives and was wondering if there was a recent change to the law that now makes it illegal to merely own a double edged blade? I know you cannot carry them on your person or in your vehicle, but the swords were found within the home and inside a bureau. They are ceremonial swords used in religious ceremonies (I don't know if that would have any relevance).