Officials are investigating two deadly Sunday shootings that could be gang-related.

The first shooting, which happened around 3:30 p.m. on the 1400 block of Vernon Road in Cedarbrook, took place after the victim had just spoken with a political candidate canvassing the neighborhood, NBC10 reported.

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The victim, a 21-year-old man, had talked to Chris Rabb, a Pennsylvania state representative candidate, right before a suspect opened fire and shot the victim twice in the head, 6ABC stated.

"Somebody walked up and deliberately shot someone with every intent of killing them," Philadelphia Police Commissioner Richard Ross described the incident to 6ABC.

The gunman, wearing a light gray hoodie, fled on foot southbound on Fayette Street, according to NBC10.

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Four hours later, a second shooting left another young man dead on the 8000 block of Temple Road, according to reports. An 18-year-old was shot once in the back and pronounced dead at Einstein Medical Center.

Police believe the second shooting was in retaliation for the earlier homicide, NBC10 added.

"I'm very frustrated by the fact that we were not able to prevent this second homicide," Commissioner Ross was quoted by NBC10. "We do believe that these are two rival factions. What they're fighting over – we haven't pinned that down right now."

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Authorities have not made any arrests in connection to the two shootings, reports stated.