Wheldon, 33, was airlifted to an area hospital after his car flew over the top of another and caught part of a fence. He died in the hospital.
The Las Vegas Indy 300 race was canceled after the crash, though racers decided to race for five laps as a salute to the fallen driver.
"IndyCar is very sad to announce that Dan Wheldon has passed away from unsurvivable injuries," IndyCar CEO Randy Bernard said in a statement. "Our thoughts and prayers are with his family today."
"I've never seen anything like it," Australian driver Ryan Briscoe, 30, told the Associated Press about the crash scene. "The debris we all had to drive through the lap later, it looked like a war scene from Terminator or something. I mean, there were just pieces of metal and car on fire in the middle of the track with no car attached to it and just debris everywhere ... your first thoughts are hoping that no one is hurt, because thereâs just stuff everywhere. Crazy."
The British driver was one of the most popular in Indy Racing. Had he won the race on Sunday, he was in line to make $5 million.
Wheldon won the Indy 500 earlier this year and in 2005.
He is survived by his wife (since 2008), Susie, and their two young sons, Sebastian, 2, and Oliver, 7 months. The family lives in St. Petersburg, Fla.
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