Four men have been charged in the death of a 9-year-old boy who was gunned down in a backyard after becoming upset with his mother and running from his Chicago home, Police Superintendent Garry McCarthy said Friday.

Derrick Allmon, 19, Jabari Williams, 22, and Michael D. Baker, 19, all face first-degree murder charges in the death of Antonio Smith, McCarthy said. Police didn't immediately release the name of the fourth suspect.

Allmon, Williams and Baker were allegedly driving around looking for rival gang members on Aug. 20. Allmon was handed a gun by Williams and ordered to shoot two men they came across, McCarthy said.

"As Allmon approached his intended targets on foot, he came across Antonio Smith in a rear yard of a residence,'" McCarthy said. "Believing that Antonio Smith was yelling a warning to his intended victims, Allmon shot Antonio Smith multiple times, wounding him fatally."

The boy was shot at least four times — killed not far from where he lived in the Grand Crossing neighborhood on Chicago's South Side.

Shortly after the shooting, the boy's mother, Brandi Murry, said her son left home after she answered "no" when he asked for a cupcake. About an hour later, he was being taken to a hospital with gunshots to the chest.

Allmon allegedly dropped the .380-caliber handgun in a nearby sewer as he fled the shooting scene, authorities said. It was recovered by investigators Thursday.

The same handgun has been traced to two other shootings this year, including another fatal one, McCarthy said.

"Unfortunately this tragic murder is yet one more example of the strife being caused by gangs and guns in our community," McCarthy said.

McCarthy emphasized the boy and members of his family have no street gang affiliation.

It wasn't immediately known if the suspects have attorneys.

McCarthy said Allmon had been arrested in 2012 on a gun charge, convicted in 2013 and sentenced to 3½ years in prison the following year. Allmon was released just weeks before the boy's death.