Officers were called to Marshall Road and Powell Lane around 1 p.m., Upper Darby police said. The victims, who were only identified as men in their 20s, died at the scene, police said.
Police on Friday evening released photos of a person of interest.
"One hundred percent targeted, 100% ambushed," Superintendent Timothy Bernhardt told 6abc.
Anyone with information is asked to contact the Upper Darby Police Department at 610-734-7693 and ask for the detective division.
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