Much of the violence unfolded between 9 p.m. Saturday and 7:30 a.m. Sunday. Twelve people were shot, including all four recorded homicides, within that time frame.
Two men were found shot, one fatally, on the city's South Side on Sunday morning, police said.
Police said the men, 30 and 27, were found on the ground outside in the Chicago Lawn neighborhood's 6100-block of South Campbell Avenue around 5:45 a.m.
The 30-year-old, shot in the head, was pronounced dead on the scene. His name was not immediately released.
The 27-year-old, shot in the torso multiple times, was transported to Christ Hospital in critical condition.
What led up to the shooting was not immediately clear.
Area One detectives are investigating. Authorities did not immediately provide further information.
Minutes earlier, a teenage boy was injured in a shooting on the city's Southwest Side on Sunday morning, police said.
Police said the shooting happened in the Gage Park neighborhood's 4900-block of South Kedzie Avenue around 5:30 a.m.
The 17-year-old was standing outside when he heard gunshots and felt pain, police said.
The victim, shot in the arm, self-transported to Insight Hospital, where he is listed in fair condition.
Police said the teen was not able to provide officers with details about the shooting.
Area One detectives are investigating. Further information was not immediately available.
Earlier Sunday morning, a man was found shot to death on the city's Far South Side, police said.
The 25-year-old was found lying on the ground in the 13100-block of South Langley Avenue around 3:40 a.m.
The victim, shot in the head, was taken in critical condition to the University of Chicago Medical Center, where he was later pronounced dead. His name was not immediately released.
What led up to the shooting was not immediately clear.
Area Two detectives are investigating. Police did not immediately provide further information.
On Saturday evening, a man was shot to death inside an SUV on the city's South Side, police said.
Police said the shooting happened in the Englewood neighborhood's 6200-block of South May Street around 9:15 p.m.
A suspect approached a gray SUV, took out a gun, and fired shots, striking a 34-year-old man inside, police said. The suspect then fled in an unknown direction.
The victim, shot in the shoulder and stomach, was transported in critical condition to the University of Chicago Medical Center, where he was later pronounced dead.
The Cook County Medical Examiner's Office later identified him as Steven Gallegos.
Area One detectives are investigating. Authorities did not immediately provide further information about the shooting.
Hours earlier, a West Side shooting killed a woman and injured two other people, police said.
Police said the shooting happened near West Fulton Street and North Long Avenue in the city's Austin neighborhood around 11 p.m.
A 48-year-old man and two women, 48 and 43, were standing outside when they heard gunshots and felt pain, police said.
The 48-year-old woman, shot in the head, was pronounced dead on the scene. Her name was not immediately released.
The 43-year-old woman, grazed in the leg, and the man, shot in the ankle, were both taken to Mt. Sinai Hospital in good condition.
Area Four detectives are investigating. Authorities did not immediately provide further information about the shooting.
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