Tributes – and soul-searching – after tragedy of British IndyCar champion British driver Dan Wheldon killed in crash at Las Vegas IndyCar race

It was the final day of the IndyCar racing season and while the serious action was being played out between title contenders Dario Franchitti and Will Power, all eyes at the Las Vegas Motor Speedway were on the car belonging to the British driver, Dan Wheldon.

As part of a special challenge designed to help rekindle the popularity of the sport, Wheldon had been offered the chance to compete for a $5m prize which he would share with a randomly selected fan. To win it, all he had to do was start from last place on the grid and overtake all 34 cars ahead of him.

It was a heady end-of-term atmosphere but one tinged with fear, drivers later admitted. For the 33-year-old former private schoolboy, whose film-star good looks and affable demeanour made him a hero with US race goers since arriving in the country in 1999 to try his luck on the notoriously perilous IndyCar circuits, it was to end in fiery tragedy.

On the 12th lap of the gruelling 300-mile race, Wheldon's car was sent hurtling skywards before exploding in flames after becoming embroiled in a horrific 15 vehicle pile-up.

Last night, as tributes were paid to the father of two who lived in St Petersburg, Florida, with his wife Susie and two boys, Sebastian, two, and Oliver, six months, questions were raised over the safety of the sport. Former IndyCar driver Mark Blundell described the tragedy as "inevitable" adding "these kind of cars shouldn't be running on these kinds of circuits." He said: "It was a recipe for disaster when you look at what was going on."

Wheldon's father Clive, speaking at the family home in Emberton, Buckinghamshire, thanked the public for "overwhelming outpouring of sympathy". He said: "Daniel was born to be a racer and left us doing what he loved to do. He was a true champion and a gentleman on and off the track."