At least five people were killed and five others injured on Sunday when a cargo plane operating on behalf of Amazon Air crashed while attempting to land at Miami International Airport, and Amazon said it is cooperating fully with the investigation.

The company confirmed to FOX Business that the aircraft involved was operated by cargo carrier 21 Air, which flies for Amazon Air. According to its website, Amazon Air is Amazon's air cargo network that moves packages between the company's facilities. Like other large cargo networks, Amazon Air does not operate its own fleet directly; instead, it relies on contracted carriers such as 21 Air, meaning safety oversight of flight operations rests with those operators while Amazon maintains its own network standards.

"We're heartbroken to learn that five people lost their lives in today's incident at Miami International Airport. Our deepest sympathies go out to the families, loved ones, and all those affected by this devastating loss," an Amazon spokesperson said.

"The airplane, which was operated by 21 Air, was attempting to land when this incident occurred. We're working closely with local authorities and officials to learn more and will cooperate fully with any investigation," the spokesperson added.

According to authorities, Prime Air Flight 7598 — a Boeing 767-300 operated by 21 Air — overran the runway while attempting to land at Miami International Airport at around 2 p.m. local time after departing San Juan, Puerto Rico. Miami-Dade officials said the aircraft struck multiple vehicles and caught fire.

Three of the injured victims were transported to a trauma center in critical condition, while two others were taken to a local hospital, authorities said.

The Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) are investigating the crash. In runway-overrun investigations, the NTSB typically examines factors such as weather conditions at the time of landing, runway surface conditions, aircraft landing weight and speed, and braking performance; final determinations of probable cause generally take a year or more to complete.

Boeing told Fox News that the aircraft was first delivered as a passenger plane in 1994 before later being converted to a freighter. Passenger-to-freighter conversions are a common practice in the cargo industry, allowing older widebody aircraft to be repurposed for package hauling, and the FAA sets inspection and maintenance requirements for such converted aircraft.

"Boeing extends our deepest condolences to the families and loved ones of those who lost their lives in the accident in Miami," the company said. "Our hearts go out to those injured and affected by this tragedy. Boeing is supporting the investigation led by the U.S. National Transportation Safety Board."

It was not immediately clear whether the crash would affect Amazon Air operations or package deliveries. Previous cargo aircraft accidents have prompted heightened regulatory scrutiny and, in certain cases, resulted in temporary operational disruptions.

The last fatal crash involving Amazon's air cargo network occurred in 2019, when an Atlas Air Boeing 767 operating for Amazon Air crashed in Texas, killing all three people aboard, officials said at the time.

21 Air could not immediately be reached by FOX Business for comment.

Fox News Digital's Bonny Chu contributed to this report.