Police said a male victim was pronounced dead on the scene, while two of the three surviving victims had life-threatening injuries. The victims were between 17 and 19 years old, police said.
A suspect, a 19-year-old from Gilroy, has been arrested and booked in jail for homicide, police said in a news release Sunday.
The altercation happened just before 1:00 a.m. at the home of Gilroy City Council Member Rebeca Armendariz, according to police.
Police have not released information on a suspect or motive in the shooting.