Any person who shall have in his possession or control any explosives, including any bomb, shell or similar device filled with one or more explosives, intending to use the same or cause the same to be used or who has used the same for an unlawful purpose shall be guilty of a high misdemeanor, and upon conviction shall be punished by imprisonment in a State prison for a term of not more than 25 years. The possession of explosives or any bomb, shell or similar device filled with explosives, without a permit as required by this act, shall be evidence of an intent to use the same or cause the same to be used for an unlawful purpose. Unlawful purpose shall mean a purpose that cannot be authorized under the provisions of this act.
N.J.S. § 21:1A-142