According to police, the crash happened just before 12 p.m. Friday near the intersection of 55th and Vine streets.
Police said a 5-year-old girl was taken to an area hospital and then airlifted to Children's Hospital of Philadelphia where she was placed in critical condition.
A 3-year-old girl was also taken to an area hospital and then transferred to CHOP via ambulance. She was placed in stable condition, police said.
A 43-year-old man also sustained injuries in the crash. He was taken to Penn Presbyterian Medical Center in stable condition.
Police found the striking vehicle in the 5300 block of Race Street. When police arrived, the truck was empty.
In video obtained by Action News, you can see the pickup truck traveling through the intersection. We paused the video before the truck hit one of the victims.
On Friday evening, Philadelphia police released an image of the wanted man.
The driver is described as a man in his 50s, who was last seen wearing a white T-shirt with dark lettering and tan pants, police said. He was last seen heading eastbound on Race Street from 53rd Street.
Anyone with information about the crash is asked to call police at 215-686-TIPS.