At least seven people were killed and 11 injured after a UPS cargo plane crashed on Tuesday in the US city of Louisville, erupting into a massive fireball shortly after takeoff, Kentucky Governor Andy Beshear said.

"The news out of Louisville is tough tonight as the death toll has now reached at least 7, with that number expected to rise," Beshear posted on X. "First responders are onsite and working hard to extinguish the fire and continue the investigation."

"Air monitoring assets have been deployed, and we are working to keep the public informed and keep folks in the area safe," he added.

What happened during the crash?

The Federal Aviation Administration (FAA) said the plane crashed at about 5:15 p.m (2215 GMT) local time.

The plane crashed "after departing from Louisville Muhammad Ali International Airport in Kentucky," the FAA said in a statement.

UPS said that the US National Transportation Safety Board was conducting an investigation into what happened.

The flight was taking off, and heading for Honolulu, Hawaii.

Broadcaster WLKY, a CBS affiliate, showed footage of the crash. The plane took off with fire on one wing, and a huge fireball broke out as it hit the ground.

Several buildings in an industrial area beyond the runway were ablaze after the crash, with thick plumes of smoke rising into the evening sky, visible from several miles away.

Louisville Metro Emergency Services said it had issued a shelter-in-place order for all locations within five miles (eight kilometers) of the airport.

Flight operations have been halted overnight, the Louisville International Airport confirmed.

What do we know about the plane?

It is unclear how the plane's engine caught fire, and how a plane with three engines in total failed to stay airborne after having lost only one.

"That airplane should have flown on two engines," aviation analyst John Cox was quoted as saying by Reuters. "So now we’ve got to look at what caused it not to fly."

Reviewing footage of the plane in flames, he added that the fire was far too large to be indicative of an ordinary engine fire.  

Records from the FAA show that the plane was a MD-11 freighter — a model acquired by Boeing following a merger with McDonnell Douglas — that was 34 years old.

Aviation system strained amid shutdown

The crash comes on the heels of the FAA raising the alarm over the mounting strain on US airports, as the record-breaking federal shutdown in the US has also left air traffic controllers working without pay.  

Chaotic scenes at key airports across the country have been increasing, as staffing and security shortages cause major flights delays and cancellations.  

On Tuesday, US Transportation Secretary Sean Duffy warned of "mass chaos" in US air travel in coming days, as the shutdown was injecting "more risk" into an already strained system.   

He added that, should the situation worsen, he would consider closing certain parts of the airspace for travel: "We will restrict the airspace when we feel it's unsafe."

Edited by: Srinivas Mazumdaru and Rebecca Staudenmaier