Other forms: muggers
Someone who steals another person's personal property after threatening to hurt them (or actually hurting them) is a mugger. Most muggers attack their victims in a public place.
To steal things from someone is to rob them, and when it happens outside on the street or sidewalk, especially with the threat of violence, the robber is usually called a mugger. A mugger might brandish a weapon or merely threaten harm, and he usually steals money, jewelry, cell phones, or other valuables. Mugger comes from the verb mug, or "beat up," which originally meant "punch in the face," from the nickname mug, or "face."