Philadelphia Mayor Cherelle Parker told a news conference that the person who died on the ground had been in a car at the site of Friday's crash.
"Thus far, our count is that there are 19 injured victims," Parker said.
Separately, Mexican President Claudia Sheinbaum said in a post on X on Saturday that she had asked consular officials to support the families of the six Mexican citizens who were on the plane and died when it crashed.
Jet Rescue Air Ambulance, based in Mexico and licensed to operate in the United States on Friday said its aircraft crashed with four crew members, one paediatric medical patient and the patient's mother on board.
The child was a girl on her way home with a final destination of Tijuana, Shai Gold, who works on corporate strategy with Jet Rescue Air Ambulance, told CNN on Friday.
Her mother was also aboard, he said.
