Background: News footage from the scene of the Oct. 31 shooting in Chula Vista, Calif. (KFMB). Insets (left to right): Kane Roldan and Elias Yanez (GoFundMe).

David Garcia, an 18-year-old, has been charged with two counts of first-degree murder and additional charges related to firearm use, including negligent discharge and carrying a loaded firearm in public. On Wednesday, Garcia appeared in court and entered a plea of not guilty. The charges stem from the deaths of 15-year-old Kane Roldan and 17-year-old Elias Yanez, who reportedly were trying to defuse a situation involving Garcia and a friend when they were shot.

Prosecutors presented their case in court, alleging that Garcia had been brandishing a gun tucked into his waistband at a house party attended by over 100 people. The scene turned deadly when tensions escalated.

According to the Times of San Diego, Deputy District Attorney Jason Yeh recounted in court that Garcia had allegedly fired his weapon into the air earlier in the evening, aiming to intimidate someone during a separate confrontation. The night’s events spiraled into a tragic loss of young lives.

According to courtroom reporting by Times of San Diego, Deputy District Attorney for San Diego County Jason Yeh said that before the altercation involving Roldan and Yanez, Garcia allegedly fired his gun into the air during another incident in an attempt to scare the person away.

Later that Halloween night, Garcia was reportedly arguing with a different partygoer who was a friend of Roldan and Yanez. Yeh said that the two teens tried to intervene, then Garcia allegedly “tragically killed these two boys.”

In a press release, the Chula Vista Police Department said that officers responded to reports of a shooting at 11:17 p.m. When they arrived, they found Roldan and Yanez with gunshot wounds and began lifesaving measures. Both teens were brought to the hospital and were pronounced dead.

Police said that Garcia was arrested on Monday. He is being held at the George Bailey Detention Facility without bond. His next court date is scheduled for Dec. 12.