Both men had been shot in the head. One victim, 25, was shot once in the back of the head and pronounced dead at the scene at 8:03 p.m.
It was the city's 40th homicide this year, according to police records. At the same point last year, the city had recorded 28 homicides.
The other man - who wasn't identified but is believed to be in his mid-30s - was shot twice in the head and taken to Albert Einstein Medical Center in "extremely critical condition," Small said.
"It's not clear whether he'll survive," Small said.
Evidence showed that the shots were either fired from inside the car or from a short distance away, Small said.
No information was available on the shooter or the motive, and witnesses were being interviewed by Homicide Unit detectives.
The shootings came six days after three men were found dead in what police called execution-style killings in a house in Lawndale. Two of the men were found bound, lying on the first floor, and the third was found in a bedroom on the second floor. Each had a gunshot wound to his head.
Earlier last night, in an apparently unrelated shooting, a 17-year-old male was shot four times about 7:15 p.m. on Edgley Street near 22nd in North Philadelphia, Small said.
The victim was hit three times in his abdomen and once in his left elbow, and was taken to Temple University Hospital, where he was listed in critical condition last night.
A witness told police that the teen was shot by a male on a bicycle as he walked on Edgley. That witness was taken to Central Detectives last night for questioning.
The victim staggered two blocks to Diamond Street near 23rd, where he collapsed in front of a store.
No information on a motive was available in that shooting, and investigators were combing through surveillance from nearby Philadelphia Housing Authority and Police Department cameras, Small said.
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