It could be days — or more — until authorities are able to confirm the number of dead and injured, said Adam Thiel, the city's managing director. As of Saturday morning, officials confirmed seven dead — six on the jet, one person on the ground — and 19 injured.

An air ambulance carrying six people crashed near a mall in northeast Philadelphia on Friday evening, the company that operates the aircraft said.

The Learjet 55 went down just after takeoff, creating what witnesses described as a massive fireball, shaking houses and leaving a chaotic street scene.