A 4-year-old boy was shot and injured when a gunman opened fire

4 Year Old Shot Barbershop, then in auto accident, police said

Officers said the barbershop was filled with kids getting back-to-school haircuts

police said it happened on the 5000 block of Rising Sun Avenue in the Olney neighborhood at about 5:15 p.m

Investigators said the gunman walked to back of crowded barbershop where an argument broke out

The child was hit in the shoulder, police said.

Officers said the gunman then ran in an unknown direction.

Police said no arrests have been made in the case.