The man sought is Shawn Timbers, 22, of the 1200 block of Alcott Street. He is described by police as a 'person of interest.'
Witnesses tell police it was around 3:30 p.m. on Tuesday when the 8-year-old girls, Eryca and Kaitlyn Bradfield, were crossing the street in the area of Colgate and Cheltenham in the Lawncrest section of the city.
They were headed to a corner store to get candy.
While in the intersection, both were hit by a man driving a gray Lincoln Town Car. Kaitlyn was run over on her midsection.
The driver fled the scene. Witnesses say they tried to catch up to the car, but the driver sped away.
Police say the car was later found parked several blocks from the scene.
The twins were taken to Saint Christopher's Hospital for Children. Kaitlyn was last reported in critical condition, while the Eryca was released from the hospital on Tuesday night suffering just bumps and bruises.
Police say the witnesses were able to get a tag number for the Lincoln. Police say they've spoken to the owner of the vehicle, and the investigation continues.
Anyone with information on Timber's whereabouts are asked to contact Accident Investigations at 215-685-3180.