PHILADELPHIA (WPVI) -- Philadelphia police said a teen robbed a Tacony pizza shop Saturday night.Police said just before 11 p.m. a 16-year-old arrived at Star Pizza on the 5800 block of Torresdale Avenue.Investigators said he demanded money and then ran out a side door down Torresdale Avenue, where the owner armed with a gun chased after him, firing a shot at the teen.Officials said the teen got into a waiting vehicle and rode away.According to investigators, the teen later showed up at Jefferson Frankford Hospital with non-life-threatening injuries.Police said he was arrested at the hospital and faces numerous charges.