(a) It shall be a misdemeanor to operate or maintain a junkyard in violation of this chapter except those junkyards lawfully in existence on May 6, 1966.
(b) It shall be the duty of the state police and the police of the cities and towns to enforce this chapter, and any persons, firm, corporation or association violating this section shall, upon conviction of the first offense, be punished by a fine of not less than fifty dollars ($50.00) nor more than one hundred dollars ($100), or by imprisonment for not less than ten (10) days nor more than thirty (30) days, or both the fine and imprisonment, and shall for a second or subsequent conviction be fined not less than one hundred dollars ($100) nor more than five hundred dollars ($500), or by imprisonment for not less than thirty (30) days nor more than six (6) months, or by both the fine and imprisonment; provided, however, that any automobile junkyard violating this section and chapter 21 of title 5, shall be prosecuted in accordance with chapter 21 of title 5, and upon conviction be subject to the penalties provided in that chapter.