The Duke of Cambridge has praised Leicester City owner Vichai Srivaddhanaprabha's "big contribution to football" after the billionaire duty-free entrepreneur was killed in a helicopter crash outside the club's King Power Stadium on Saturday.
William, president of the Football Association and a keen football fan, said he was "lucky" to have known Mr Srivaddhanaprabha "for several years" as tributes continued to flood in for the Thai businessman and the four other victims.
He joined Prime Minister Theresa May in sending his thoughts to the victims' families, friends and the supporters.
In a statement, the Duke said: "I was lucky to have known Vichai for several years.
"He was a businessman of strong values who was dedicated to his family and who supported a number of important charitable causes.
"He made such a big contribution to football, not least through Leicester City's magical 2016 season that captured the imagination of the world.
"He will be missed by all fans of the sport and everyone lucky enough to have known him."
Mrs May said that the "outpouring of grief is a testament to how many people's lives were touched by those on board".
Police confirmed Mr Srivaddhanaprabha was killed along with two staff members, the pilot and a passenger when the aircraft fell from the sky and burst into flames outside the King Power Stadium at about 8.30pm on Saturday.
The four others are believed to be Nursara Suknamai and Kaveporn Punpare, pilot Eric Swaffer and passenger Izabela Roza Lechowicz.
The air accident watchdog is carrying out an investigation into what caused the aircraft to crash in a car park near the stadium a few hours after the Foxes drew 1-1 with West Ham.
Hundreds of tributes were left outside the ground on Sunday by mourners, with more messages flooding in through social media.
Leicester City issued a statement late on Sunday describing the businessman, who bought the club for £39 million in 2010 and led it to a first Premier League title, as a "great man".
The club said: "In Khun Vichai, the world has lost a great man. A man of kindness, of generosity and a man whose life was defined by the love he devoted to his family and those he so successfully led.
"Leicester City was a family under his leadership. It is as a family that we will grieve his passing and maintain the pursuit of a vision for the Club that is now his legacy."
The club will set up a book of condolence at the stadium from Tuesday morning for supporters to pay their respects, with an online version on its website for those unable to visit in person.
Leicester's EFL Cup tie against Southampton and the development squad's match against Feyenoord in the Premier League International Cup on Tuesday have both been postponed.
The Air Accident Investigation Branch (AAIB) is leading the investigation into how the Agusta Westland AW169 helicopter crashed in what is believed to be the first accident involving an AW169 aircraft.
A spokesman added: "A team from the AAIB has been deployed to the site and is investigating. Anyone with information that might be helpful to the investigation is asked to contact the police."
Witnesses said the helicopter seemed to spiral out of control moments after it set off from the pitch.
But pilot Mr Swaffer has been hailed as a hero for steering the spinning aircraft away from crowds of people on the ground.
The tragedy is being described as the "darkest day" in Leicester City's history and mourners began laying wreaths near the stadium on Sunday morning.
Bouquets, flags and football shirts were left outside the ground by members of the public, alongside a large image of the Hindu god Ganesh which was propped up amidst the flowers.
Messages from Leicester fans on the flowers included "In our thoughts!!" and "Thank you xx", and one fan left a card of a fox with their flowers, which read: "Thinking of you all."
Wembley Stadium posted an image on Twitter of the stadium lit up in the blue and white colours of Leicester City.
Players paid tribute on social media to Mr Srivaddhanaprabha, who became chairman of the club in 2011 and is known for arriving and leaving the stadium in his helicopter at home games.
Goalkeeper Kasper Schmeichel said he was "totally devastated and heartbroken" by the news and added: "It is difficult to put into words how much you have meant to this football club and to the city of Leicester.
"We now have a responsibility as a club, as players and fans to honour you. From knowing you we do this by being the family you created."
Leicester and former England striker Jamie Vardy described Mr Srivaddhanaprabha as a "legend" and an "incredible man who had the biggest heart".
Self-made Thai billionaire Mr Srivaddhanaprabha was very highly thought of in the city.
Under his ownership the club rose out of the Championship and eventually won the Premier League for the first time in its history in 2015-16, defying odds of 5,000-1.
He was also involved in charity work, donating £2 million towards a new children's hospital.
The Polish embassy described Ms Lechowicz as "a wonderful pilot".
A statement said: "It is with great sadness that we received news of the death of Izabela Lechowicz in the Leicester helicopter crash. She was a wonderful pilot and a #Polka100 campaign finalist who created a positive image of Poland in the UK. Our deepest condolences to her family."
"Our thoughts today are with the families of those who have sadly died, with Leicester City Football Club, and with both football supporters and the wider local community who have all been impacted by the events and the news that those on board the aircraft have not survived."
Superintendent Steve Potter said it was likely to take several days to complete the investigation around the crash site.