A 15-year-old boy has been charged with the fatal shooting of another teenager Sunday in southwest suburban Joliet.

He was charged Tuesday with murder and unlawful possession of a weapon, according to Joliet police.

At the time of his arrest, he was also charged with aggravated battery with a firearm, defacing identifying marks on a firearm, aggravated unlawful use of a weapon, unlawful possession of ammunition and use of a weapon without a FOID card, police said in a statement.

Officers responding to reports of shots fired about 6:15 a.m. found 17-year-old Alejandro Mendoza with a gunshot wound inside a vehicle near Elwood Avenue and Creed Street, according to police and the Cook County medical examiner’s office. He was taken to Silver Cross Hospital in Joliet before being airlifted to Loyola University Medical Center in Maywood.

Mendoza, who lived in Joliet, was pronounced dead at Loyola at 1:32 p.m., according to the medical examiner’s office. An autopsy found he died of a gunshot wound to the chest and his death was ruled a homicide.

Initial reports indicated the shots were fired in the 600 block of Chase Avenue, a few blocks from where Mendoza was found, police said. A home on that block had been hit by gunfire. Investigators found a loaded firearm and arrested the 15-year-old.

Police said the case is “an ongoing investigation and is still in its early stages.”

Authorities are asking anyone with surveillance video recorded between 5:30 and 6:30 a.m. Sunday in an area bordered by Collins Street, the Canadian National railyard, Williamson Avenue and Jackson Street to call Detective Michael Cagle at 815-724-3035 or the Joliet Police Investigation Unit at 815-724-3020.

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