Chicago South Side shooting injures 13, including 3-year-old (VIDEO)

A late night shooting in Chicago's South Side wounded 13 people, including a three-year-old boy who remains in critical condition after he was injured in the cheek, according to CBS News.

Two more victims were also in critical condition.

The violence broke out in waves. First, after six p.m. on Thursday, four people were wounded, and then sometime after 10 p.m. the second wave of gunfire began. Some 60 police officers and 10 ambulances responded.

Police say the shootings could be gang-related.

"I can tell you that it's an ongoing investigation and that 13 people were shot," Chicago Police Department spokeswoman Amina Greer said on Friday. "At this time, we believe the motive for the shooting to be gang-related," she added.

A witness, Julian Harris, told the Chicago Sun-Times newspaper that dreadlocked men fired at the group from a gray sedan.

"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."

The youngest victim, 3-year-old Deonta' Howard, remains at Mount Sinai Hospital in critical condition.

His grandmother Semecha Nunn told the Chicago Tribune that the little boy was heavily sedated.

"He tried to get up and go, he’s not trying to be pinned down by nobody," she said.

"He’s not your average 3-year-old," she continued. "He’s very smart, he’s beyond his years. I don’t know if you’ve heard the saying, 'He’s an old soul.' That’s the best words to describe him. He’s an old soul."

Chicago has suffered a plague of gun violence in the last few years, with more than 500 murders in 2012, according to the FBI.

The shooting on Thursday night comes after a mentally unstable contract worker and former Navy reservists shot and killed 12 people on Monday in the Navy Yard in Washington, DC.

Watch the CBS report here: