WCAU-TV ( http://bit.ly/19nhTtB) says the 20- and 21-year-old women were walking home from a Juniata convenience store when two men demanded money.
Police said they obliged, but one man opened fire, and the 21-year-old woman was hit in the side and back. She was rushed to Temple University Hospital in critical condition.
Chief Inspector Scott Small said both men fled, but a suspect was arrested a block away hiding under a truck and a gun was found next to him. The second suspect got away.
Small said investigators will try to find out why the man opened fire even after the victim gave him money.
Information from: WCAU-TV, http://www.nbc10.com