According to authorities, Derrion Albert was kicked, punched and beaten to death by several teens near the Agape Community Center.
Police say about a dozen teens were in a massive fight with sticks around 2:30 p.m. Albert got dragged into the mob.
Albert was taken to Advocate Christ Medical Center in Oak Lawn and pronounced dead around 6:30 p.m. Thursday.
Witnesses say the fight that Albert appeared to have walked into was between mostly students from his school, Fenger High, identified by the uniforms they wore.
"These were kids beating kids," said Milton Massie, director, Agape Community Center.
The community center's surveillance cameras caught the beating death of Albert who was walking from Fenger High School.
"It looked like 100 kids. We're talking about kids all over the place, in every direction...On the video, there were kids hopping over cars. The kids had huge sticks. They were going after each other. It seemed as if it was not so much a targeted, but it was random," said Massie.
"Everyone was just letting him get beat...it was basically like he was really by himself," said Tynesha Jackson, witness.
"He was down and they started kicking him. Then I saw they had, like two-by-fours, that's when we realized that someone need to do something," said Linda Cotton, Agape Community Center.
The center employees pulled Albert's beaten body to safety.
"He would gasp for a breath a few times but he was unconscious and lying there," said Cotton.
Now police are reviewing surveillance video from a camera at the center. And Albert's grandparents are pleading for action.
"The people that did this, they need to come forward and tell us why they did it and turn themselves in," said Jesse, Albert's paternal grandmother.
His grandfather, Joseph Walker, showed ABC7 his grandson's photographs and academic achievement awards.
Walker raised Albert, who was a dedicated student. Walker says Albert was walking home from school at the time of the attack and did not know the people in the riot. He and police believe Albert was an innocent victim who got caught in the middle.
"He was in Bible class this Tuesday night, church on Sundays. I had no trouble out of my grandson whatsoever. This thing that happened to him is so horrific, we just don't know what we're going to do. We've lost a really dear friend in my grandson. He was a blessed child," said Walker.
Massie, who says his community center has been in Roseland for 30 years, says this type of fight has become more common recently as two groups from Fenger have escalated the violence between them.
Meanwhile, Albert's grandfather says he's just trying to understand why.
"I don't know where all this anger comes from these people today. That's just too much anger for someone to have in their heart. All I can do is pray for these people. I'm going to pray for forgiveness," said Walker.
The medical examiner has officially ruled Albert's death a homicide, saying he died from blunt head trauma.
Ron Huberman, Chicago Public Schools CEO, said counselors will be on hand to help the students and the family.
Police say no one is in custody.