A 48-year-old Murrieta man died Wednesday night near El Dorado Park after attacking another man, and police said the slaying may have been self-defense.

Police said the 48-year-old suspect confronted the other man around 10:30 p.m. in the 7400 block of East Willow Street and unexpectedly attacked him with a metallic cable.

The victim’s parent, who called the police, intervened and helped his son subdue the suspect “in an effort to stop the attack,” police said.

When officers arrived at the scene, they located the suspect unconscious and in a homeless encampment, according to the Long Beach Police Department.

Officers attempted to resuscitate him, but when Long Beach Fire Department personnel arrived at the scene, they determined that he was dead, authorities said.

Following the attack, police interviewed the victim, who suffered non-life-threatening injuries to his upper body and was transported to a local hospital, the LBPD said. His parent, who suffered minor injuries and was treated at the scene, also cooperated with the investigation.

A motive was not immediately known, but detectives believe everyone involved knew each other.

The suspect’s identity was not revealed as the Los Angeles County Coroner’s Office works to notify his next of kin.

Detectives are still investigating and working to determine the manner of his death, the LBPD said.

Editor’s note: This story has been updated with more details from the Long Beach Police Department.

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