The most recent one occurred at about 1:20 a.m. Wednesday.
A 61-year-old woman was shot by a paintball gun in Englewood on the South Side. She was standing on the sidewalk in the 6100-block of South Ashland Avenue, when someone in a passing red SUV fired a paintball gun at her, striking her in her hand, Chicago police said.
She refused treatment, police said. Area One detectives are investigating.
In the other two cases, police said someone in a white sedan fired at the victims.
No one was seriously injured.
A 34-year-old man was shot by a paintball gun Tuesday in West Town on the Near West Side.
About 10 p.m., he was riding his bicycle on the street in the 1800-block of West Hubbard Street, when someone in a passing red sedan fired a paintball gun at him, Chicago police said.
He was struck in the right arm and groin area, police said. He refused treatment.
About a minute later, a man was walking his dog near Morgan Street and Monroe Street, when someone inside a passing white sedan fired a paintball gun at him, striking him multiple times, police said. He refused treatment.
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On Sept. 10, two men were shot by paintballs in the 700-block of South Michigan Avenue in the South Loop. A 29-year-old was shot in his eye and taken to Northwestern Memorial Hospital in fair condition, police said. The second man was struck in the chest but not injured.
Doctors recently put out a new warning about a surge in paintball attacks involving people in moving vehicles and people walking on sidewalks.
Typically, eye surgeons at the University of Chicago Medical Center see one paintball-related eye injury every few months. But as a result of this disturbing trend, doctors there said they treated as many as eight patients in one weekend.
Authorities are warning others about a dangerous pattern: Paintball attacks on pedestrians in Chicago have sent several to the hospital with serious eye injuries.
"It is very rare to see seven to eight severe eye injuries of any sort within a weekend, much less of the same kind," said Dr. Hassan Shah, an ophthalmologist at University of Chicago Medical Center.
Shah said the injuries treated over the past weekend could impact patients for life.
"These injuries do range from bleeding inside the eye and vision loss to where the eye actually ruptures - and we saw that whole range during this weekend," Shah said.
The University of Chicago's police department said it received eight reports of paintball attacks in the past several days, similar to previous attacks reported over the past few weeks.
"High velocity paintball injuries can be severely damaging to eyes and it will often result in permanent vision loss," Shah said.
Shah said some of the patients treated last weekend needed surgery and others suffered vision loss, which could be permanent.
Sun-Times Media contributed to this report.