NORTH PHILADELPHIA - Philadelphia Police are investigating a shooting in North Philadelphia that left a 13-year-old boy in critical condition.Officials say police responded to the 2200 block of North Woodstock Street Saturday night, about 7:15, on the report of a shooting.Responding officers found the 13-year-old boy with a gunshot wound to his head.Police rushed him to a nearby hospital where he is listed in critical condition.AdvertisementPolice say a firearm was located at the scene, but no arrest have been made..