Police have identified the17-year-old who turned himself into police as the Rittenhouse Square gunman whoallegedly shot a good Samaritan last week. Mehdi Fraiji, of the 900 block of South 15th Street, is being charged as an adult with attempted murder, aggravated assault, robbery, firearms violations and related offenses, CBS Philly reported. The charges stem from an Oct. 18 incident when a 39-year-old cyclist was riding through the park and happened upon a robbery in progress. Two men were sticking up an 18-year-old woman and a 22-year-old man, police said. When the cyclist intervened, Fraiji allegedly took a revolver from his accomplice and fired several shots, Philly.com reported. Then, the pair ran off. Police responded to multiple calls in the park just after 9:30 p.m., when they found the victim laying on a walkway. He was taken to HahnemannUniversity Hospital, where he was treated for wounds to his torso and shoulder. Fraijisurrenderedat the police stationaround 4 a.m. Saturday, and was accompanied by his father.Police were able to identify the teen as a suspect because the couple in the robbery attempt knew him by his nickname.