Police say Lynelle Flowers, 26, and Zahir Randall, 21, were taken into custody earlier this week.
They are charged with the murder of 22-year-old Tariq Scott Jr.
The Chester County District Attorney said Randall drove Flowers to where Scott lived on Valley Road in Sadsbury Township on June 22.
The district attorney said Flowers shot Scott as he sat in a car.
Investigators say Flowers is the father of Scott's sister's two children.
They say Scott's sister had recently told Flowers she was leaving him, and he beat her up.
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