Joel German Mercado, 16, was shot and killed during a back-to-school house and pool party in Covina on the night of August 16, 2025. The party had drawn well over a hundred teenagers after heavy promotion on social media. Around 10 p.m. shots rang out in the quiet subdivision; teens fled and Mercado was struck. He was taken to a hospital and pronounced dead from a gunshot wound.

Police converged on the 600 block of East Camellia Drive near Peachtree Lane about 10:15–10:22 p.m., found a discarded weapon in the street, and used helicopters and K-9 units to sweep the area. Investigators described an argument among minors that escalated into an exchange of gunfire; some partygoers were detained for questioning but no arrests were announced immediately. Family and neighbors gathered at a memorial and relatives launched a fundraiser in his memory.

On September 8 authorities charged a West Covina man, saying prosecutors allege he and a 16-year-old companion—identified as Mercado of La Puente—allegedly tried to rob partygoers, which prompted an attendee to return fire and fatally hit Mercado in the chest. What details about the sequence of events that night can anyone who was there or has information add?