Four men accused in the shooting death of a teenager last week on the southwest side have been arrested.

The San Antonio Police Department said the alleged retaliation at the Valley Ridge mobile home park was over a stolen backpack.

Suspects 19-year-old Damien Walker, 18-year-old David Zamora, and 17-year-old Milo Mendez are accused of showing up to 18-year-old Joseph Silva's mobile home in masks and shooting him multiple times.

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A fourth suspect Samuel Ayala was arrested later that day. Ayala said Silva pistol-whipped him and stole his backpack three days before the murder.

The confrontation left Silva dead after being shot in the chest.