RIVERSIDE (CBSLA) — The family of a 13-year-old boy who died from injuries sustained during an on-campus fight has filed a claim against the Moreno Valley School District.

Diego Stolz was killed after being during a fight as a result of being bullied by two boys at Landmark Middle School.

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A Moreno Valley teen is the face of bullying after a video of him being sucker punched and knocked to the ground fatally injured him. (credit: Diego’s family)

Cell phone video of Monday’s assault showed two boys punching Diego in the face by a boy in a black t-shirt outside the school’s main building.

Diego was said to have suffered a major traumatic brain injury and never regained consciousness.

Los Angeles-based plaintiff trial law firm Taylor & Ring filed a wrongful death claim against the Moreno Valley Unified School District on behalf of Diego’s guardians, Juana Salcedo and Felipe Salcedo.

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The claim asserts that the District has a long history of student altercations on its campuses, failed to take bullying complaints by Diego’s family seriously and failed to enforce anti-bullying policies to protect its students.

“It is appalling that the school, which is supposed to protect its students, failed to address aggressive bullying that was occurring on its school grounds, even after multiple complaints were made,” said lead counsel Ring. “This gross incompetence by the school and its administrators led to the death of a young boy, who was subjected to horrific abuse while the administrators looked the other way. The family is devastated by the loss of Diego.”

Representatives for the family claimed that days before Diego’s death, he sustained serious harassment and bullying, both physically and verbally, and sought help from a science teacher.

The Moreno Valley Unified School District was said to promote a “Bully-stop 360” program, which claims to educate its students, teachers, and parents on bullying and bullying prevention.

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A statement from the Moreno Valley Unified School District read in part:

“In response to argument on MVUSD’s liability: This claim alleges the District is legally liable for Diego’s death. That is not the case. The two boys who attacked and killed Diego are responsible for this death.”