An Amazon-branded cargo plane crashed just outside Miami International Airport (MIA) on Sunday afternoon after overrunning the runway during landing, killing at least five people and injuring five others in one of the deadliest cargo-aviation accidents on U.S. soil in years. The Boeing 767-300, operated for Amazon by contract carrier 21 Air, struck multiple vehicles on a road bordering the airport before catching fire, sending a column of thick black smoke over South Florida.

The National Transportation Safety Board (NTSB) has dispatched a full investigative team to Miami, and the crash has triggered widespread flight disruptions that were still rippling through the airport into Monday morning.

According to a statement from the Federal Aviation Administration (FAA), 21 Air Flight 7598 - operating under the Prime Air brand - overran the runway shortly before 2 p.m. local time on Sunday after arriving from Luis Muñoz Marín International Airport in San Juan, Puerto Rico. Miami-Dade County Sheriff Rosie Cordero-Stutz said the aircraft overshot Runway 30, the airport's diagonal runway, before crossing onto a roadway near Northwest 42nd Avenue that is used by warehouse workers and nearby businesses.

The plane struck multiple vehicles, including two semi-trucks, before coming to rest in a field beside the road. Images from the scene showed the aircraft resting on its belly, largely intact despite the fire that had broken out around its engines. A truck driver who was loading cargo nearby, identified as Romierkys Rodriguez, described watching the aircraft come down and hearing an explosion he said he could feel from where he stood.

Preliminary tracking data cited by multiple outlets, drawn from Flightradar24, indicated the aircraft was still travelling at roughly 128 miles per hour when it departed the end of the runway - a speed far higher than what a jet would typically carry that late in a landing roll.

Miami-Dade Fire Rescue Chief Raied "Ray" Jadallah said five people were confirmed dead and five others were hospitalized, three of them in critical condition and taken to a trauma centre, with two others receiving treatment for less severe injuries at a local hospital. Officials said it was not immediately clear whether those killed had been aboard the aircraft or in the vehicles it struck on the ground.

The crash trapped the plane's pilot and co-pilot inside the cockpit, and several occupants of the vehicles that were hit also became trapped, according to Jadallah. Rescue crews additionally had to extricate one person pinned beneath a vehicle. Miami-Dade County Mayor Daniella Levine Cava said fire and rescue personnel reached the site within seconds of the crash, and roughly 200 Miami-Dade Fire Rescue personnel, drawn from more than 60 units, were deployed to fight what Jadallah called a highly complex fire involving the aircraft's engine compartments.

Hazardous-materials crews also worked to contain a fuel leak from the wreckage and to safely power down the aircraft's engines, fire officials said.

In a statement, Amazon spokesperson Kelly Nantel said the company was heartbroken over the five lives lost and extended sympathy to the families and loved ones affected. 21 Air CEO Keith Winters separately said the airline was devastated by the accident and was cooperating fully with federal investigators as the circumstances of the crash remain under investigation.

The NTSB confirmed it is sending a team to Miami headed by Chairwoman Jennifer Homendy, who is expected to hold a press briefing on the investigation. Early scrutiny is centring on the exact point at which the aircraft touched down. Aviation experts told reporters that a landing jet is typically expected to touch down within the first 3,000 feet, or roughly 914 metres, of a runway; video circulating from the scene appeared to show the Boeing 767 remaining airborne well beyond that zone before finally settling onto the tarmac.

Aviation safety expert Steve Arroyo said that if the aircraft had indeed floated past the standard touchdown zone, standard procedure would have called for the crew to abandon the landing and circle back for another attempt rather than continuing to touch down. Mary Schiavo, a commercial pilot and former Inspector General of the U.S. Department of Transportation, pointed to a tailwind as a factor that could compound the danger of an aircraft that has already used up a significant portion of the runway before touching its wheels down.

Schiavo also said investigators would likely examine the aircraft's maintenance history in detail, noting that the 32-year-old jet had passed through several owners over its service life, including a period of foreign ownership by a Russian company, before its conversion from a passenger aircraft to a freighter in 2015. The plane had originally flown passengers for multiple airlines for more than two decades before that conversion.

Adding to the safety questions, aviation reporters noted that MIA is not equipped with an engineered material arresting system — a bed of crushable material installed at some U.S. runway ends specifically designed to stop an aircraft that overruns the pavement.

The crash forced Miami International Airport into a full ground stop within minutes. U.S. Transportation Secretary Sean Duffy said on social media that the ground stop had been ordered so first responders could safely assess the wreckage, and he urged travellers to brace for significant delays and possible cancellations. All four of MIA's runways and its taxiways were shut down as of 3 p.m. Sunday, with the closure later extended to 5:30 p.m. before two runways were reopened that evening.

The disruption was significant given the timing, arriving during the Labor Day holiday weekend, one of the busiest windows of the year for U.S. air travel. Tracking service FlightAware reported that more than 160 flights in and out of MIA were cancelled and close to 325 were delayed by Sunday night. The disruption carried into Monday, with FlightAware data showing 129 domestic flights delayed and 65 cancelled by mid-morning, as only two of the airport's four runways remained operational. Some flights were diverted to Orlando International Airport, more than 200 miles to the north, airport officials said.

Passengers described long waits and repeated rebooking. One traveller told local broadcasters she had been rescheduled three times before her flight was finally cancelled outright, leaving her without another option until Tuesday.

Sunday's accident is the latest in a string of incidents involving Amazon-linked cargo operations in recent years, reviving scrutiny of safety practices among the contract carriers that fly for the retail giant's Prime Air network. Amazon does not operate its own cargo jets directly; instead, it relies on a small group of contract carriers, including 21 Air, to fly its air-freight network under the Prime Air brand — a structure that places day-to-day operational and maintenance responsibility with the contractor rather than Amazon itself.

For now, officials have not released the names of those killed or injured, and the full sequence of events — including cockpit voice and flight data recorder readouts once retrieved — will take weeks or months to be reconstructed into a formal NTSB finding. Investigators have cautioned that determining a definitive cause, whether pilot decision-making, a mechanical or braking failure, weather factors such as tailwind, or some combination of these, will require the full scope of the federal probe.