CHICAGO — A 3-year-old boy who was among 13 people wounded in a late-night attack on a southwest Chicago park was alert when he arrived at the hospital and was apparently doing well, his family and friends said early today.

The attack late Thursday in the city’s Back of the Yards neighborhood left three victims, including the boy, in critical condition. The others were reportedly in serious or fair condition.

The child’s uncle, Julian Harris, told the Chicago Sun-Times that dreadlocked men in a gray sedan shot at him Thursday night before turning toward nearby Cornell Square Park and opening fire. He said his nephew was shot in the cheek.

“They hit the light pole next to me, but I ducked down and ran into the house,” Harris said. “They’ve been coming round here looking for people to shoot every night, just gang-banging stuff. It’s what they do.”

Police officials declined to discuss details of the investigation. Ron Gaines, a department spokesman, said no arrests had been made.