Police say Andre Alejandro, 22, went into the pizzeria around 2:15 a.m. and started yelling gang slogans before the shooting. He left briefly after a verbal altercation, retrieved a gun and fired through the open door of the restaurant, police say. He then fled east on Foster.
Ivan Alanis, 14, was struck in the face and taken to Illinois Masonic Hospital in critical condition, where he was later pronounced dead.
There were no other injuries reported.
Alanis was eating pizza with his sister and her friend in the 5100-block of North Broadway at the time of the shooting.