MARTINEZ -- A Contra Costa County jury on Tuesday convicted two men of murder in the death of a 16-year-old Oakley boy fatally shot at an Antioch house party in 2011.

The jury deliberated for a day and a half before finding Leon Moreno, 21, and Ricky Mendoza, 20, guilty of first-degree murder and a special allegation that they were gang members when Mendoza shot and killed Martin Navarro on Aug. 20, 2011, prosecutor Danielle Douglas said. The jury also found true that Mendoza used a handgun.

It was the second trial for the defendants, whose first trial in March ended in a hung jury. That time, they were tried alongside Tony Martin, 20. In this trial, Martin testified against them in exchange for the promise of a plea deal in which he's anticipated to be sentenced to 10 years for Navarro's death.

Martin shot a 17-year-old girl in the shoulder at the party where Navarro was killed, and he is still awaiting trial on charges that he killed 27-year-old Ever Osorio in a Concord park in August 2011.

Douglas said Navarro was killed because the defendants and their fellow gang members believed him to be a rival gang member and a "snitch" based on the statements of his ex-girlfriend Jessica Juarez, who is awaiting trial on murder charges in the case.

Two other members of the gang have already taken plea deals. Carlos Guzman, 19, was convicted of accessory to murder and a gang enhancement and sentenced to five years in prison. Christopher Donaldson, 23, was convicted of voluntary manslaughter and sentenced to 10 years.

Mendoza, whose attorney argued that he was not the shooter that night, is facing life in prison without the possibility of parole. Moreno's attorney told jurors that Moreno was not armed that night and was not part of a plan to kill anyone. He's facing 40 years to life in prison.

They are scheduled to be sentenced July 19.

Follow Malaika Fraley at Twitter.com/malaikafraley.