An Amazon-branded cargo jet careened off the runway and slammed into a cluster of vehicles at Miami International Airport on Sunday afternoon, erupting into flames and grounding the airport's entire runway system on one of the busiest travel weekends of the fall.

Prime Air Flight 7598, a Boeing 767-300 cargo plane operated on Amazon's behalf by contract carrier 21 Air, was arriving from Luis Muñoz Marín International Airport in San Juan, Puerto Rico, when it overran the runway around 2 p.m. ET, according to NPR. The aircraft skidded off the northwest end of a diagonal runway and struck several vehicles near NW 42nd Avenue before catching fire, sending a column of black smoke over the airfield that was visible for miles.

Ground Stop, Hundreds of Delays

Miami-Dade Fire Rescue dispatched more than 60 units to the scene and reported "multiple patients," though officials had not confirmed the extent of injuries or whether anyone was killed as of Sunday evening. Airport officials ordered a full ground stop, closing every runway and taxiway; roughly 250 flights were delayed at MIA in the aftermath, compounding travel headaches for holiday-weekend passengers across the airport's dozens of domestic and international routes.

A review of air traffic control audio cited by CNN found the flight crew did not declare an emergency before landing, raising early questions about what went wrong in the final moments of the approach.

"OUR ABSOLUTE PRIORITY IS THE SAFETY, WELL-BEING AND CARE OF EVERYONE INVOLVED."

Amazon spokesperson Kelly Nantel confirmed the incident in a statement, saying an "Amazon Air plane operated by 21 Air experienced an incident while attempting to land at Miami International Airport today," and that the company was "doing everything we can to support those affected."

Transportation Secretary Sean Duffy said the Federal Aviation Administration was sending investigators to the scene, and the National Transportation Safety Board is expected to lead the crash probe — a process that typically involves recovering the plane's flight data and cockpit voice recorders before any preliminary findings are released, often weeks later.

A Fleet Under the Microscope

The 767-300 is a workhorse of Amazon's fast-growing air cargo network, which the company has expanded aggressively in recent years to compete with UPS and FedEx on next-day and same-day delivery promises. Sunday's crash is likely to draw renewed scrutiny to the maintenance and safety practices of the third-party contract carriers, like 21 Air, that Amazon leases aircraft and crews from to fly those routes.

MIA is one of the country's busiest gateways for both passenger and cargo traffic, particularly to Latin America and the Caribbean, making the runway closures especially disruptive. Investigators will need to determine whether mechanical failure, pilot error, weather, or some combination of factors caused the overrun. Airport officials have not said when normal runway operations will fully resume, and the disruption is expected to ripple through the remainder of the Labor Day travel week.