The McDonnell Douglas MD-11F went down soon after departing Louisville Muhammad Ali International Airport, leaving a fiery trail and a towering column of black smoke visible for miles.

Governor Beshear warned that the number of casualties could rise as recovery efforts continue.

Louisville Mayor Craig Greenberg said the three crew members aboard are presumed dead, while four of the confirmed victims were on the ground.

Fire officials said hundreds of firefighters have nearly contained the fire that spread over “a massive area.”

Crews are creating a “formal grid” to search for additional victims, they added.

The National Transportation Safety Board will lead the investigation, according to the Federal Aviation Administration.

An airport official said an NTSB team of at least 28 investigators is expected to arrive in Kentucky on Wednesday.

Boeing, which merged with McDonnell Douglas in 1997, said it has offered technical assistance to the NTSB.

“Our concern is for the safety and well-being of all those affected,” Boeing said in a statement. “We stand ready to support our customer and have offered technical assistance to the NTSB.”

Security footage from Kentucky Truck Parts & Service showed the explosion triggered by the crash, which occurred about 500 feet from the business.

The company said on Facebook that while its employees were unharmed, “many of our neighbors and people in the surrounding area were hurt, and properties were badly damaged.”

Louisville Fire Chief Brian O’Neill said the crash sparked “secondary explosions” at a nearby petroleum recycling facility, where storage tanks containing propane and oil ruptured.

He explained that some noises thought to be explosions were actually pressure relief valves activating as designed.

“It can sound very scary, but that’s a good thing. That means the relief valve worked, and it didn’t actually explode,” O’Neill said.

Governor Beshear said the Kentucky Petroleum Recycling facility appeared to have been “hit pretty directly.”

Chief O’Neill noted that while the blaze is “controlled and contained,” the surrounding area remains hazardous due to fuel and oil leaks.

“We’ll be there for a while handling that scene,” he said.

Authorities said the crash caused extensive damage to multiple nearby businesses.