Police say the shooting happened Monday about 5:30 a.m. The name of the Milwaukee boy who was killed was not released.
Authorities say the suspect was one of four people who tried to rob a group of victims. One victim pulled out a handgun and fired, killing the suspect. The other three suspects fled.
Police say the 30-year-old West Allis man who shot the teen has been released from custody.
Milwaukee police have arrested five additional suspects believed to be part of a group responsible for dozens of robberies over the past several days.