Gruesome weekend for Chicago leaves city, police chief reeling - Note for a lecture, "E Pluribus Unum? What Keeps the United States United"

By Holly Yan and Leslie Holland, CNN

Chicago police: 7-year-old killed amid weekend violence 01:22

Story highlights

• A 7-year-old son of a gang member is shot and killed
• Police superintendent: A broken system and a rampant gun flow fuel the violence

(CNN)When a city has seven killings in two days, including the death of a 7-year-old boy, something is systemically wrong.

That's what Chicago's police chief said after a spate of bloodshed that tormented the city over the weekend.

"We need to repair a broken system," Police Superintendent Garry McCarthy told reporters Sunday. "Criminals don't feel the repercussions of the justice system."

Take, for example, the death of 7-year-old Amari Brown. McCarthy said the boy was the unintended victim of bullet meant for his father, a ranking gang member.

The system failed Amari, the police chief said. Amari's father, who has been arrested 45 times and has a lengthy criminal record, should not have been on the streets, McCarthy said.

"If Mr. Brown is in custody, his son is alive," McCarthy said. 

At a vigil Sunday for Amari, family friend Michael Singleton told the media that unless real changes are made, the cycle of violence will continue.

"All of you all will be back out here next week, on another corner, filming the same thing, from somebody else, saying exactly what I'm saying," he said.

"So I'm tired of doing news conferences. I'm tired of listening to them. I'm tired of talking about them. Until we make a better decision as a community and as a city, this is all that's going to happen."

A gruesome weekend

Even with a 30% increase in the number of police on the streets over the holiday weekend, seven people were killed between Friday morning and Sunday afternoon, the superintendent said.

Another 40 people were wounded in weekend shootings, McCarthy said.

And since Friday morning, Chicago police have recovered one illegal gun per hour across the city, McCarthy said.

"We must stem the flow of guns into the city," he said.

This year's statistics may sound staggering, but compared with last year, the number of violent incidents is actually down. For the same period in 2014, there were 64 shootings, 69 nonfatal victims in those incidents and 15 slayings.

McCarthy said he is incredibly proud of the men and women of his department amid the challenges they face every day.

But "we need some help here, folks," McCarthy said. "We have to fix this broken system."

The CNN Guns Project -- One day of gun violence

CNN's Vivian Kuo and Rick Martin contributed to this report.