The helicopter crash in which Leicester City owner Vichai Srivaddhanaprabha died was "one of the most horrendous things anybody could ever see", says former England keeper Peter Shilton.
Ex-Leicester player Shilton and wife Steph witnessed the crash outside King Power Stadium on Saturday.
Two members of staff, the pilot and a passenger were also killed after the aircraft spiralled out of control.
"It will live with us forever," Shilton told the BBC.
The 69-year-old said the helicopter "seemed to be making a funny noise and started to spin" above them as they were walking to their car following the 1-1 draw with West Ham.
"It was surreal and we weren't sure what was happening, but then it started to spiral. We realised it was out of control and all of a sudden it started coming towards us," he said.
"Steph was panicking and it was shock, fear and all of a sudden it seemed to drop a bit and then crash - it all happened so quickly."
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Shilton said the helicopter then burst into flames. A team investigating Saturday's crash, which happened at about 20:30 BST, have recovered the aircraft's digital flight data recorder.
Leicestershire Police named the other people who died in the crash as Nursara Suknamai, Kaveporn Punpare, pilot Eric Swaffer and his partner Izabela Roza Lechowicz.
Shilton added: "My wife became hysterical. I was in shock, I think I still am. I grabbed hold of her. She wanted to do something, but obviously we couldn't.
"The police arrived very quickly, then the fire engines came and we were so helpless.
"The image keeps coming back to me of the helicopter spiralling down.
"Knowing it was the chairman and thinking it could've been the whole family in there made it even worse - even though it couldn't really be any worse."
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'We will be in mourning for a long time'
Srivaddhanaprabha's wife, Aimon, and son, Aiyawatt, laid a wreath in the middle of the pitch at the stadium on Monday before embracing the Leicester players and staff gathered around the centre circle.
Goalkeeper Kasper Schmeichel earlier led his team-mates in paying tribute to the owner that many of them referred to as "The Boss".
Shilton, who was born in Leicester and made over 300 appearances for the Foxes between 1966 and 1974, said the city "will be in mourning for a long time".
Srivaddhanaprabha bought Leicester in 2010, helping them to win promotion to the top flight in 2014 before the club claimed the 2015-16 Premier League title - despite odds of 5,000-1 - in one of the greatest sporting stories of all time.
During his stewardship of the club, he also donated £2m to the Leicester Children's Hospital charity, £1m to the Foxes Foundation for community causes and £1m to Leicester University's medical department.
"Leicester has lost a great man who did so much for the city," said Shilton.
"Thankfully the rest of the family weren't in the helicopter so his legacy will carry on, but he will be so sadly missed.
"We feel deeply for the rest of the family but there is so much respect for what he's done for the club."