An 18-year-old man accused of gunning down two teenage boys at a house party pleaded not guilty Wednesday to two counts of murder.

David Garcia is accused of opening fire on 15-year-old Kane Roldan and 17-year-old Elias Yanez at a Halloween night party attended by more than 100 people.

Police responded to an East Prospect Street near Castle Park High School at 11:15 p.m. Friday to find both boys with gunshot wounds. Both victims were taken to UC San Diego Medical Center, where they were later pronounced dead, police said.

Garcia was arrested Monday near his home in National City, police said.

Along with the murder counts, he faces a charge of negligently discharging a firearm for allegedly shooting into the air some time before the teens were shot. He also faces a special circumstance allegation of committing multiple murders.

If he is convicted of the murder counts, plus the special circumstance allegation, he would face life in prison without the possibility of parole or the death penalty, should prosecutors pursue capital punishment.

At Garcia’s arraignment, Deputy District Attorney Jack Yeh said Garcia showed multiple people at the party that he had a gun tucked into his waistband.

Prior to the fatal shooting, the prosecutor said Garcia got into an altercation with someone, then fired the gun into the air to scare the person away.

Later, Garcia allegedly got into an altercation with a friend of the victims. When they attempted to aid their friend, Garcia shot them both, Yeh said.

Garcia remains in custody without bail. Police say they believe there are no other suspects at this time but added that more arrests are possible as the investigation continues.

Georgina Martinez, Roldan’s foster mother, told NBC 7 that Roldan and Yanez bonded over basketball in elementary school and continued to play travel ball. She says they were at her house with a group of friends Friday night, and she remembers the fun they had as they left for the party.

“They were always goofing off,” Martinez said. “I replay in my head, and the videos of them outside right before they left … Can’t believe that was the last time.”

The family of Kane Roldan are remembering him after he was killed at a Halloween Party in Chula Vista on Halloween night, reports NBC 7’s Kelvin Henry.

NBC 7’s Omari Fleming contributed to this report.