Officers were dispatched to the 5900 block of Palmetto Street at about 3:35 p.m. on April 28, authorities wrote.
At the scene, three male victims aged 15 to 20 were found with multiple gunshot wounds and pronounced dead, the department said. Their names were not reported as of Friday evening.
A fourth victim, identified as a 16-year-old boy, was shot once in the chest and driven to Jefferson Frankford Hospital where he was placed in critical condition, they added.
Police have not reported any arrests in connection with the killings.
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