569.160. 1. A person commits the crime of burglary in the first degree if he knowingly enters unlawfully or knowingly remains unlawfully in a building or inhabitable structure for the purpose of committing a crime therein, and when in effecting entry or while in the building or inhabitable structure or in immediate flight therefrom, he or another participant in the crime:
(1) Is armed with explosives or a deadly weapon or;
(2) Causes or threatens immediate physical injury to any person who is not a participant in the crime; or
(3) There is present in the structure another person who is not a participant in the crime.
2. Burglary in the first degree is a class B felony.
(L. 1977 S.B. 60)