Story highlights

NEW: The father of a slain 7-year-old isn't cooperating with police, Chicago's top cop says

NEW: "I'm worried that the next shooting will occur in retaliation," the police superintendent says

A broken system and a rampant gun flow fuel the violence, he says

CNN  — 

When a city has eight killings in two days, including the death of a 7-year-old boy, something is seriously wrong with the system.

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 a 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.

Existing laws, McCarthy said, made it easy for the man to get out of jail the day after he was arrested on a firearms charge in April.

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

According to McCarthy, the father isn’t cooperating with investigators looking into his son’s killing.

“He gave us a statement, but it was a vanilla statement that he didn’t see anything. You know, I can’t reveal the circumstances that we know occurred at that scene at this time, but he could do a lot better for us, let’s put it that way. And you know, the fear is, he’s going to take care of it himself,” McCarthy told CNN’s “AC360.” “So while we’re being held accountable for violence here in the city, and I accept our accountability, as a cog in the wheel, there’s a much bigger picture here. If he wasn’t on the street, the shooting doesn’t occur. Now that he is on the street, I’m worried that the next shooting will occur in retaliation.”

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.

Even in a city frequently beset by headline-grabbing violence, seven slayings between Friday morning and Sunday afternoon drew terrible attention.

Since Friday morning, his police officers have recovered one illegal gun per hour across the city, according to McCarthy.

“We need to repair a broken system. Criminals don’t feel the repercussions of the justice system,” McCarthy said.

This year’s statistics may sound staggering, but compared to last year, the number of violent incidents is 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.”

CNN 2014 Guns Project – One day of gun violence

CNN’s Vivian Kuo, Rick Martin, Catherine E. Shoichet and Christopher Lett contributed to this report.