Twelve-year-old Laron Williams was shot and killed around 2 p.m. Thursday on the 700 block of E. Locust Avenue in the city's Germantown section.
Two other men, 30-year-old Khalif Chambers and 47-year-old Riley Darden, also died in the shooting.
"We know that the two adult males were hit right at the top of the block, right by Crowson (Street), where they were found by police. It appears the juvenile was able to run towards his residence and was found a short distance away from the adults," said Deputy Commissioner of Investigations Frank Vanore.
At least 12 shots were fired at the scene, according to police.
Philly police provide update on deadly triple shooting
Police believe the shooters were driven to the scene and left in the same vehicle. Investigators are reviewing video to develop a description of the suspects.
Sources tell Action News Williams was celebrating his birthday the day he was killed.
He is now among at least 154 victims in the same age group who have been shot so far this year, including 27 who were shot and killed.
Anyone with information on the suspects is asked to call police at 215-686-TIPS.
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