A small plane has reportedly crashed at Southend Airport in Essex.
Essex Police said it was at the scene of a “serious incident”.
Images posted online showed a large cloud of black smoke, with one witness saying they saw a “fireball”.
A police statement said: “We were alerted shortly before 4pm to reports of a collision involving one 12-metre plane.
“We are working with all emergency services at the scene now and that work will be ongoing for several hours.
“We would please ask the public to avoid this area where possible while this work continues.”
Essex County Fire and Rescue Service said four crews, along with off-road vehicles, attended the incident.
Four ambulances and four hazardous area response team vehicles are at the scene, the East of England Ambulance Service said.
An air ambulance has also been sent to Southend Airport, it added, in a statement which described the incident as “still developing”.
Four flights scheduled to take off from the airport this afternoon have been cancelled, its website says.
According to flight-tracking website Flightradar, two planes that had been due to land at Southend have been diverted to nearby airports London Gatwick and London Stansted.
David Burton-Sampson, the MP for Southend West and Leigh, posted on social media: “I am aware of an incident at Southend Airport. Please keep away and allow the emergency services to do their work.
“My thoughts are with everyone involved.”
Local councillor Matt Dent said on X: “At present all I know is that a small plane has crashed at the airport. My thoughts are with all those involved, and with the emergency services currently responding to the incident.”
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