Mo. Rev. Stat. § 570.023: Robbery in the first degree — penalty.

1. A person commits the offense of robbery in the first degree if he or she forcibly steals property and in the course thereof he or she, or another participant in the offense:

(1) Causes serious physical injury to any person; or

(2) Is armed with a deadly weapon; or

(3) Uses or threatens the immediate use of a dangerous instrument against any person; or

(4) Displays or threatens the use of what appears to be a deadly weapon or dangerous instrument; or

(5) Steals any controlled substance from a pharmacy.

2. The offense of robbery in the first degree is a class A felony.