Emergency services have raced to the scene of a small plane crash at London Southend Airport.

No details on where the plane was heading or how many people were on board were immediately disclosed.

In a statement on social media, the airport confirmed a “serious incident” involving what it termed a general aviation aircraft.

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It later said that all flights to and from the airport have been cancelled until further notice, while police, emergency services and air investigators assess the incident.

British media said it was a medical transport jet equipped with medical systems for transporting patients, specifically a Beechcraft B200 Super King Air heading to the Netherlands.

Soon after the crash, images circulated on social media showing a plume of fire and black smoke emanating from the crash site. The plane involved is said to be 12m long.

Witness John Johnson, who was at the airport with his family, said he saw a “big fireball” after the plane “crashed head first into the ground”.

“It took off and about three or four seconds after taking off, it started to bank heavily to its left, and then within a few seconds of that happening, it more or less inverted and crashed just head-first into the ground,” he said. “There was a big fireball.”

Johnson said that before the plane got into position for take-off, he and his family waved at the pilots and “they all waved back at us”.

After the crash, Johnson said the airport’s fire service responded straight away, with two fire engines sent to the crash site, followed by local police, ambulance and fire services.

Essex Police said it was alerted just before 4pm Sunday local time to the “serious incident” at the relatively small airport, which is around 72 kilometers east of the capital.

“We are working with all emergency services at the scene now and that work will be ongoing for several hours,” Essex Police said.

The local member of Parliament, David Burton-Sampson, urged people to stay away and let the emergency services do their work.

“My thoughts are with everyone involved,” he said.