Television and unverified footage shared on social media showed the Japan Airlines (JAL) airliner moving along the runway before a large eruption of orange flames and black smoke burst from beneath and behind it.

Video posted to social media platform X showed people sliding down an inflatable emergency slide from the side of the passenger plane, while flames shot out from the rear of the aircraft.

Tokyo plane collision: French forensic experts to probe accident that killed 5

Keith Mackey, an international aviation safety consultant based in Florida, said an investigation will determine how the coastguard plane was able to be on the runway at the same time.

“The runway should have been clear,” he said, adding it is unclear if the coastguard plane was on its take-off roll, possible on an intersecting runway or still taxiing before take-off when the collision occurred.

“While military and civilian aircraft do operate under some different rules, those involving air traffic control are the same” he said, adding that the planes were probably using different radio frequencies.

After all passengers and crew had left the plane, dozens of fire engines attempted to douse the flames – but failed to extinguish the blaze that soon engulfed the entire aircraft.

Mackey praised the JAL crew for their ability to evacuate the passengers, but was stunned by other aspects of the rescue.

“I’m a bit surprised as to why the interior of the aeroplane is burning so furiously, as it should have very little flammable material in its construction.

“I’m also surprised by the apparent lack of firefighting trucks and personnel that should have been able to quell the flames,” he said.

The JAL plane, reportedly an Airbus 350, had arrived from New Chitose Airport serving Sapporo on the northern island of Hokkaido. Those on board included eight children.

“Smoke began to fill the plane, and I thought, ‘this could be really bad’”, an adult male passenger told reporters at the airport.

“An announcement said doors in the back and middle could not be opened. So everyone disembarked from the front,” he said.

A female passenger said it had been dark on board as the fire intensified after landing.

“It was getting hot inside the plane, and I thought, to be honest, I would not survive,” she said in comments shown on broadcaster NHK.

The coastguard plane had been preparing to fly to Ishikawa prefecture to deliver supplies after the devastating New Year’s Day earthquake, which killed at least 48 people.

Prime Minister Fumio Kishida praised the deceased crew members on their way to help the victims of the quake.

“These were employees who had a high sense of mission and responsibility for the affected areas. It’s very regrettable,” he told reporters.

“I express my respect and gratitude to their sense of mission,” Kishida said.

Haneda suspended domestic flights, according to its website, but most international take-offs and landings were still operating.

A spokesman for Airport Authority Hong Kong said at least five flights operating between Hong Kong International Airport and Haneda Airport had been affected.

“Passengers travelling between the two airports today and tomorrow are advised to check with airlines for flight status updates, and confirm their flights before heading to Hong Kong International Airport,” the spokesman said on Tuesday.

One of those affected was Cathay Pacific Airways flight CX542 which was scheduled to land in Tokyo at 9:15pm on Tuesday but was forced to head back to Hong Kong shortly after passing Taiwan.

The Post has reached out to Cathay for comment.

Travel agency EGL Tours’ executive director Steve Huen Kwok-chuen said no customers from either group or individual tours had been affected by the fire in Haneda Airport.

“Our customers travelling to Tokyo usually land at Narita Airport, while those travelling to Hokkaido typically have direct flights to Sapporo. There is rarely a need for transit through Haneda,” he said.

Hong Kong’s Immigration Department said that as of 8pm on Tuesday, it had received requests for help from 10 Hong Kong residents who had been aboard the Japan Airlines plane and that they were safe. The department said it would refer their cases to the Chinese embassy in Japan to provide help.

Hongkongers who require help can contact the Immigration Department’s 24-hour hotline at (+852) 1868, use its 1868 hotline through the mobile app, or send messages to the 1868 WhatsApp hotline.

‘Pretty frightening’: survivors recall experience of powerful Japan quake

A Japanese transport ministry official said investigations into the incident were ongoing, including exchanges between the flights and air traffic control.

Japan has not suffered a serious commercial aviation accident in decades.

Its worst ever was in 1985, when a JAL jumbo jet flying from Tokyo to Osaka crashed in central Gunma region, killing 520 passengers and crew.

That disaster was one of the world’s deadliest plane crashes involving a single flight.

Additional reporting by Lars Hamer, Oscar Liu, Maria Siow, Danny Mok