SOUTH LOS ANGELES (CBSLA) – An investigation is underway into the beating death of a 23-year-old father at a music festival at Exposition Park earlier this month.

On Dec. 14, Kalvin Sanchez was assaulted while attending the Rolling Loud Festival being held at Banc of California Stadium.

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Kalvin Sanchez hospitalized after the attack. (GoFundMe)

He suffered a serious head injury and was rushed to Dignity Health-California Hospital Medical Center, the Los Angeles County Coroner’s Office reports. He passed away on Dec. 18.

An autopsy determined that Sanchez died of subdural hematoma and blunt force head trauma. The manner of death was deemed a homicide, the coroner’s office reports.

An undated photo of Kalvin Sanchez. (GoFundMe)

We were devastated, it’s never easy losing somebody,” Sanchez’s uncle Marlon Guzman told CBS2 Monday. “We’re all just trying to keep ourselves strong and being there for each other.”

Sanchez left behind a 3-year-old daughter and a 2-month-old son.

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The exact circumstances of the assault were not confirmed. It’s unclear if Los Angeles police have identified any suspects in the case or a motive. Cell phone footage of several fights which broke out at the festival were posted to social media.

“The only thing really keeping us together is making sure that we provide a better tomorrow for his family and for his two little ones,” Guzman said.

The Rolling Loud Festival provided CBS2 with the following statement:

“We extend our deepest condolences to the family and friends of Kalvin, who passed away last week. Our fans are part of our extended family and their health and safety is our number one priority. The incident is under active investigation by both LAPD and CHP and, as such, we are unable to comment further.”

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Sanchez’s family has established a GoFundMe page to help cover funeral expenses.