At least seven people were killed and 19 were injured when an air ambulance crashed to the ground on a busy Philadelphia street, creating what witnesses described as a massive fireball and a chaotic s

The plane took off, reached about 1,500 feet of altitude and then plummeted in a steep descent, crashing less than a minute after takeoff in what National Transportation Safety Board chair Jennifer Homendy called a “high-impact crash” that left the plane “highly fragmented.”