In Chicago's Englewood neighborhood, police say two of their officers were chasing a man with a gun and when the man turned and pointed it at them, the officers opened fire.
The suspect has not been identified.
Police say officers in the 3rd District were in the Park Manor for an unrelated incident when they saw someone running out of an alley.
"At 3:45 or so, a 3rd District car was just finishing up from a call, driving south on Indiana. Saw an individual come out of the alley with a gun in his hand. Officers got out, chased him on foot. The individual turned with the weapon and at the officers. Officer fired in fear of his life. The offender was hit," said Pat Camden, Fraternal Order of Police.
The other shooting happened in west suburban Maywood where police say their officer shot a man after the man pulled a gun.
Investigators say the officer was responding to a call when he saw the gunman running into a building and followed, where the shooting took place.
The suspect has not been identified in that case either.
The 20-year-old Maywood man was pronounced dead at Loyola University Medical Center a short time after an officer shot him once in the chest inside an apartment building about 4:30 p.m., authorities said.
Police had been called to an apartment building in the 1800 block of South 19th Avenue for unspecified reasons, said Maywood village spokesman Larry Shapiro.
The Sun-Times Media Wire contributed to this report.