A. A person commits burglary in the first degree if such person or an accomplice violates the provisions of either section 13-1506 or 13-1507 and knowingly possesses explosives, a deadly weapon or a dangerous instrument in the course of committing any theft or any felony.
B. Burglary in the first degree of a nonresidential structure or a fenced commercial or residential yard is a class 3 felony. It is a class 2 felony if committed in a residential structure.