Detectives say Asbiel Copado was gunned down outside the same home where 24-year-old Eric Guzman was shot to death late last month.
Authorities believe both victims were members of the same gang. They're having a difficult time getting witnesses to come forward.
Merced County Sheriff Mark Pazin said, "Here's the thing that absolutely perplexes me again, no one sees anything, no one hears anything except the gunshots, and then persons are clamoring law enforcement to do something."
The teen's family gathered near the crime scene Tuesday, but did not want to speak on camera.