Jun 12, 2013, 11:25 PM EST
Leffler, 37, was involved in an accident at the five-eighths mile high-banked dirt track. According to NBC Philadelphia, he had to be extricated from his car and taken by air to Cooper Trauma Center, where he succumbed to his injuries.
Leffler was a veteran of the NASCAR ranks, and a one-time starter in the Indianapolis 500 (2000). He made his first NASCAR Sprint Cup Series start of the season this past Sunday in Pocono, Pa., finishing last.
He won twice in nearly 300 starts in the second-tier NASCAR Nationwide Series, and also had a single win in the NASCAR Camping World Truck Series. His 2007 Nationwide win at the Indianapolis Raceway Park was the first for the Toyota Camry in that series. He was also the predecessor to Denny Hamlin in the No. 11 FedEx entry at Joe Gibbs Racing, driving for Gibbs in 2005.
A statement from NASCAR said the following: ““NASCAR extends its thoughts, prayers and deepest sympathies to the family of Jason Leffler who passed away earlier this evening. For more than a decade, Jason was a fierce competitor in our sport and he will be missed.”
He is survived by his only son, Charlie.
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