It had been transporting a cleaning crew within the airport perimeter and had seven people inside.
The aircraft then hit a small Toyota SUV on a road just outside the airport fence.
The flight was operated by 21 Air LLC as a sub-contractor of Amazon. Before it hit the cars, it also struck navigational equipment at the airport.
Homendy said the agency didn’t have access to the aircraft yet because recovery operations were ongoing. The flight data recorder and cockpit voice recorder had been recovered and were being flown to NTSB headquarters in Washington DC for downloading.
NTSB had 32 people investigating the accident who would be on scene for at least a week, Homendy said.
Two runways remained closed as recovery work continued.
AFP reported that Homendy refused to discuss the health status of the plane’s two pilots, adding: “We do want to interview the crew.”
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