The shooting follows a wave of gun violence that hit Chicago over the last two days.
"The police was chasing my son here tonight. And they shot him. They shot and killed my son," said Cassandra Miller.
Miller says her 25-year-old son Willie was shot by police Friday night as he ran away from officers who arrived at the scene of a party near Ohio and Homan. Police news affairs said one of their mobile strike units was patrolling the area when they saw a large crowd disturbance on the street. Whether this was the result of the party getting out of hand and spilling outside it's not immediately clear, but police say that when they arrived the crowd began to disperse. That is when they say they saw Miller begin to walk away carrying a handgun.
Officers gave chase northbound on Christiana and into the west alley. They say that is where Miller turned and pointed his weapon at pursuing officers. Police said at this point, one of the officers fired and fatally wounded Miller.
Miller's mother and sister, who was also at the party, dispute this version of events and said he did not have a gun.
"...He didn't have no weapon. He didn't have no weapon at all. That's a lie right there. He was just running. They got mad because they couldn't catch him," said Miller.
Police say they recovered a weapon at the scene and an ambulance was never called because Miller was killed instantly.
In another police-involved shooting, a 50-year-old man was killed. Officers say they shot the man after he pointed a shotgun at them near 114th Street and Indiana at approximately 11:15 a.m. Saturday.
The man's name has not been released.
Both shootings are under investigation by the Independent Police Review Authority.
The police-involved shootings come on the heels of a news conference yesterday at 66th and Marshfield in Englewood, where Police Superintendent Jody Weis vowed to crack down on illegal parties, or gatherings that spill out onto the street as a way to curb the shooting spree that's taken place over the couple of days.