Stephanie Gonzalez, 17

Stephanie Gonzalez, a 17-year-old Latina, was shot and killed Saturday, June 11, in the 8500 block of Cedros Avenue in Panorama City, according to Los Angeles County coroner’s records.

Shortly after 7:30 p.m., Gonzalez and her 13-year-old sister, Kimberly Gonzalez, were found with gunshot wounds in an apartment, said Los Angeles Police Det. Richard Wheeler. The assailant, who is the ex-boyfriend of the girls’ mother, was also found with a gunshot wound to the chest.

The teenagers' mother had broken up with the 46-year-old man about a month ago, and that evening, he showed up to the apartment. He and the girls' mother got into an argument, and the man shot his ex-girlfriend in the stomach, police said.

The woman’s 20-year-old son intervened, and the man shot at him, grazing his back, Wheeler said. The son ran out of the apartment to get help.

When the son came back, the man had shot the two sisters and turned the gun on himself. All three were pronounced dead at the scene.  The man was not the girls' father.

The mother and her son were injured but are expected to survive, Wheeler said.

Anyone with information is asked to call the LAPD’s Valley homicide bureau at (818) 374-9550. Those who wish to remain anonymous can call Crime Stoppers at (800) 222-8477.

Contact the Homicide Report. Follow @nicolesantacruz and @latimeshomicide on Twitter.

Times staff writer Matt Hamilton contributed to this report.