Roberto Madrigal, 18, charged in shooting death of boy, 13, on NW Side

CHICAGO (WLS) -- Roberto Madrigal, 18, was charged Friday in the shooting death of Anthony Diaz, 13, in Chicago's Belmont Cragin neighborhood.

Madrigal allegedly shot and killed the 13-year-old boy around 10:30 p.m. Sunday near the intersection of West Grand Avenue and North McVicker Avenue.

In court Friday, Madrigal was charged with first-degree murder, accused of shooting and killing Diaz, prosecutors say.

"They were there to watch two females who were going to fight," said Assistant State's Attorney Jamie Santini. "Those females have been involved in an ongoing conflict via social media and texts. During those post attacks, it was agreed between the two females that they would meet and have a physical fight."

Diaz's family says he had left his home Sunday night to follow his sisters, ages 15 and 17, who were meeting the girls they were fighting with on Facebook.

The group met in a parking lot in the 6000-block of West Grand Avenue to fight over a post on the social media site.

Anthony Diaz, 13. (Photo courtesy of victim's family)

A melee broke out between the group of people, prosecutors say. As Diaz began to walk away, court documents say Madrigal went after him, pulled out a gun and started firing.

The 13-year-old boy was shot in the chest. He was taken to Mount Sinai Hospital, where he later died.

His family says now that two teenaged lives are forever changed, they just want the violence to end.

"We are not here to retaliate," said stepfather Ralph Otero. "This could have been avoided and we're just asking for peace."

Madrigal, of the 2700-block of North Laramie Avenue, was charged with first-degree murder and could face life in prison. He is due in bond court on Friday.