[Video of Crash](https://www.youtube.com/watch?v=Z56sZBd_H7Y) Authorities sifted through burned cars and charred debris Saturday to gather clues that might explain why an air ambulance exploded into a fiery ball as it crashed to the ground in Philadelphia, leaving no survivors on board. The small plane carrying six people, including a child who had just undergone treatment at a hospital, crashed onto a busy intersection just after takeoff from the small Northeast Philadelphia Airport. Authorities couldn’t say why the jet crashed and Adam Thiel, the city’s managing director, said it could be days — or more — until authorities are able to confirm the number of dead and injured. As of Saturday morning, officials confirmed seven dead — six on the jet, one person on the ground — and 19 injured. Spokespersons for hospitals treating the injured, Temple University Hospital-Jeanes and Jefferson Health, said most of the patients they saw had been treated and released by midday Saturday, but at least three were admitted and remain hospitalized. The crash scene was a large area, and authorities were working to assess the damage, Thiel said. Teams were going house to house inspecting the dwellings in the area. The plane crashed near Roosevelt Mall in a densely populated area.