Four people have died after a plane crashed and exploded shortly after taking off from London Southend Airport.
The medical transport aircraft had dropped off a patient and was beginning its journey back to the Netherlands when it crashed at about 3.48pm on Sunday.
Two Dutch pilots and a Chilean nurse were among those on board, according to a passenger listing document.
The deceased were all foreign nationals, Essex Police said.
John Johnson, who was at the airport with his wife and children, said he saw a “big fireball” exploding across the sky as the plane plunged “head first into the ground”.
“We all waved at the pilots, and they all waved back at us,” he said.
“The aircraft then turned 180 degrees to face its take-off, powered up [and] rolled down the runway.
“It took off and about three or four seconds [later] 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.”
Mr Johnson added: “There was a big fireball. Obviously, everybody was in shock [after] witnessing it.”
Chief Superintendent Morgan Cronin said the plane “got into difficulty” shortly after taking off and “crashed within the airport boundary”.
He added: “Sadly, we can now confirm that all four people on board died.
“We are working to officially confirm their identities. At this stage, we believe all four are foreign nationals.”
Ambulances and fire crews were also called in.
Southend Airport said it would be “closed until further notice” and urged people to contact their airlines.
Its staff are “working closely with the emergency services and air accident investigators”.
Zeusch Aviation, based at Lelystad Airport in the Netherlands, confirmed its flight SUZ1 had been “involved in an accident” at the airport and its thoughts were with “everyone who has been affected”.
The plane involved is reportedly a Beech B200 Super King Air with twin-propellers.
The Air Accidents Investigation Branch said a “multi-disciplinary team” arrived at the site on Sunday afternoon.
Lisa Fitzsimons, a senior investigator, said it is “too early to speculate” on what may have caused the crash.
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‘Airport in lockdown’
Wren Stranix, 16, from Woodbridge in Suffolk, was in another aircraft waiting to take off for Newquay in Cornwall with her family and boyfriend when the plane came down.
They watched as the emergency services arrived and were unable 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.”
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EasyJet, one of only a few airlines to use the airport, said all its remaining flights to and from Southend had been “diverted” or were “no longer able to operate”.
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”.
Sir Keir Starmer, the prime minister, said it was “terrible news that four people [had] tragically lost their lives” and he thanked the emergency services.
Essex Police is asking anyone with information or footage to get in touch.
Mr Cronin said: “In these very early stages it is vital we gather the information we need.”
