Authorities say the suspect, identified in official documents as Alexader Crawford, 31, fatally shot security guard Jave Garanganao, 41, earlier this week.
Crawford was trespassing at a student housing building in the 300 block of West Adams Boulevard just after midnight on Dec. 27 when Garanganao, working as a security guard, asked him to leave, according to the Los Angeles County District Attorney's Office.
Garanganao followed the trespasser off the property, at which point Crawford allegedly drew a gun and shot the guard multiple times.
At the scene, yellow evidence markers appeared to indicate as many as a dozen shell casings on the sidewalk after the shooting.
The suspect fled the scene but an arrest was made later that day, when officers found Crawford sleeping in a parking area near the scene of the shooting.
The LAPD later said the suspect had a handgun in his possession which was recovered. Investigators later determined the gun was the same caliber as the weapon that killed Garanganao.
A GoFundMe page was created to help Garanganao's 13-year-old daughter.
Detectives reviewed surveillance video and determined the person they took into custody was the suspected shooter, police said. He was identified as Crawford and booked for suspicion of murder.
Los Angeles County District Attorney George Gascón's office announced on Friday that a murder charge had been filed, as well as possession of a firearm by a felon.
"Mr. Garanganao was just trying to do his job when he was tragically killed," Gascón said. "My heart goes out to the victim's family and friends who have endured such a tremendous loss during the holiday season. My office's Bureau of Victim Services will provide them the services and resources they need moving forward."
Security guard killed near USC may have been shot during trespassing dispute, police say
City News Service contributed to this report.