A person believed to be in their 80s was the reported shooter, sources say.
A 22-year-old woman was shot in the legs and taken to Christ Hospital in stable condition.
Police said a man was taken into custody and taken to a hospital for evaluation.
The gunman was believed to be barricaded inside.
Some CTA service has been impacted by street closures in the area.
111 111th/King Drive buses are temporarily rerouted via King Drive, 103rd, Cottage Grove, 107th, and King Drive.— cta (@cta) March 20, 2018