Southend Airport has been closed until further notice after a small plane crashed - as video footage emerged showing the aftermath of a huge fireball.
Images posted online showed large flames and a cloud of black smoke following the incident on Sunday afternoon.
Essex Police said it responded to "reports of a collision involving one 12-metre plane" shortly before 4pm.
"We are working with all emergency services at the scene now and that work will be ongoing for several hours," the statement said.
"We would please ask the public to avoid this area where possible while this work continues."
Southend Airport said on Sunday it would be "closed until further notice" due to the "serious incident".
"We ask that any passengers due to travel tomorrow via London Southend Airport contact their airline for information and advice," it added.
It has been reported that the plane involved in the incident is a Beech B200 Super King Air.
According to flight-tracking service Flightradar, it took off at 3.48pm and was bound for Lelystad, a city in the Netherlands.
Pilots 'waved' to families watching planes
One man, who was at the airport with his wife and children, told Sky News the plane crashed within seconds of taking off.
John Johnson said the pilots "waved" at his family as they taxied the aircraft.
"We all waved [back] at them," he continued. "They carried on taxiing to their take-off point and turned around.
"Then they throttled up the engines and passed by us. The aircraft took off and within a few seconds it had a steep bank angle to its left."
The aircraft then "almost seemed to invert and unfortunately crashed," he said. "There was a large fireball."
'Airport was in lockdown'
Wren Stranix, 16, from Woodbridge in Suffolk, was in another aircraft waiting to take off for Newquay, Cornwall, with her family and boyfriend when the plane came down.
They watched from their aircraft as the emergency services arrived and were not able to leave their seats.
"The flight attendant didn't know what was going on," she told Sky News. "They said the plane had exploded and they didn't know if it was safe or not. The airport was in lockdown."
They were eventually allowed back in the terminal to wait before all flights were cancelled.
Southend Airport said the incident involved "a general aviation aircraft".
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After the incident, EasyJet - one of just a few airlines that uses the airport - said all of its remaining flights to and from Southend had been "diverted to alternative airports or are no longer able to operate".
The airline said it has contacted customers who were due to travel today. Anyone due to fly tomorrow should check online for up-to-date information, it added.
Essex County Fire and Rescue Service said four crews, along with off-road vehicles, have attended the scene.
The East of England Ambulance Service said four ambulances, four hazardous area response team vehicles and an air ambulance had been sent to the incident.
David Burton-Sampson, the MP for Southend West and Leigh, asked people to keep away from the area and "allow the emergency services to do their work" in a post on social media.
Transport Secretary Heidi Alexander said she was "monitoring the situation closely and receiving regular updates".
(c) Sky News 2025: Fireball at Southend Airport after small plane crashes