Amazon said it would temporarily pause its relationship with 21 Air, the cargo airline operating a Boeing 767 that overshot a runway at Miami International Airport on Sept. 6, killing five people and injuring five others. The plane, operating as Flight 7598 on behalf of Amazon Air, collided with two vehicles, including a van owned by an airline cleaning company. Kelly Nantel, an Amazon spokeswoman, said safety remains the company's top priority and the decision followed a review of the accident's circumstances. Amazon expects minimal impact on customers.

21 Air, based in Greensboro, N.C. and owned by billionaire Jim Crane, who also owns the Houston Astros, said it remains confident in its safety policies and is working with the N.T.S.B. investigation. DHL, which also uses 21 Air, said it continually assesses its provider relationships but declined further comment.

According to the N.T.S.B., one pilot warned the other multiple times about "excessive speed" during landing. The plane was moving at 138 m.p.h. when brakes released, and a go-around was called about 16 seconds after apparent touchdown. Former 21 Air employees have raised safety concerns in a whistle-blower case filed with the Labor Department. A final N.T.S.B. report could take a year or more.