New dashcam footage has emerged of the shocking moments a cargo plane crashed and exploded after takeoff in Kentucky, US, killing least 12 people, including a child.

A truck driver was sitting inside his vehicle, parked at Louisville Muhammad Ali International Airport, Louisville, when the plane careened into view.

The dashcam shows the driver’s stunned reaction as the plane, tipped on its side, skids along the bitumen, with a trail of towering flames.

The plane can be heard coming to a crashing stop off screen as the driver shouts in disbelief: “Ohhh s–t! Oh my f–king god!”

The inferno consumed the enormous aircraft and caused smaller explosions at Kentucky Petroleum Recycling.

The plane slammed into an auto salvage yard, killing a child who was with a parent at the business.

Authorities on Thursday revealed the cause of the aviation tragedy.

They said the plane’s left wing caught fire and an engine fell off.

After being cleared for takeoff, a large fire developed in the left wing, said Todd Inman of the US National Transportation Safety Board.

The plane gained enough altitude to clear the fence at the end of the runway before crashing just outside the airport on Tuesday afternoon (local time).

Airport security video “shows the left engine detaching from the wing during the takeoff roll”, Inman told reporters.

The cockpit voice recorder and data recorder were recovered, and the engine was discovered on the airfield, Inman said.

The plane with three people aboard was departing for Honolulu. Those among feared dead were people who were in the vicinity of the crash at UPS Worldport, the company’s global aviation hub.

First responders are searching for more victims a day after the crash.

Inman said so far there was no evidence of a link between the accident and a 36-day US government shutdown that has strained air traffic control.

US Representative Morgan McGarvey praised firefighters who rushed headfirst to the disaster scene, describing it as “hotter than hell and raining down oil”.

Louisville Mayor Craig Greenberg announced on social platform X the death toll had risen to 12, saying authorities were still looking for a handful of other people but do not expect to find anyone else alive.

University of Louisville Hospital said two people were in critical condition in the burn unit. Eighteen people were treated and discharged at that hospital or other health care centres.

The crash and ensuing fires also forced a shutdown of the airport for the night and disrupted airport-based operations at the UPS Worldport facility, slowing delivery services. UPS said it was “terribly saddened”.

The hub employs more than 20,000 people in the region, handles 300 flights daily and sorts more than 400,000 packages an hour.

Governor Andy Beshear said an emergency relief fund, typically used to help people in natural disasters, is accepting donations to help with funeral expenses and other hardships.

“In Kentucky, we grieve together and we support one another,” Beshear said.

Eric Richardson stood outside a police training academy, where people gathered waiting for word of their missing loved ones on Tuesday night.

He said his girlfriend, who had been at a metal recycling business near the explosion, wasn’t answering her phone. Her phone’s live location said she was still there.

“We don’t even want to think about anything but the best,” a friend, Bobby Whelan, said. “All our friends were there.”

Jeff Guzzetti, a former federal crash investigator, said a number of things could have caused the fire as the UPS plane was rolling down the runway.

“It could have been the engine partially coming off and ripping out fuel lines. Or it could have been a fuel leak igniting and then burning the engine off. It’s just too soon to tell,” Guzzetti said.

-with AAP/Reuters