(CNN) -- IndyCar said it has launched an investigation into the 15-vehicle wreck that claimed the life of driver Dan Wheldon and expects to have preliminary findings within weeks. The organization said Wednesday individual members of various motorsports bodies will help it determine factors involved in the fiery incident Sunday at the Las Vegas Indy 300. IndyCar said it had incorrectly stated Tuesday that the Automobile Competition Committee of the United States (ACCUS) and the Federation Internationale de l'Automobile (FIA), the national and international governing organizations, were formally involved in the investigation. The violent crash raised fresh questions about safety, both in motor sports, generally, and at the Las Vegas track, specifically.
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Public memorial service for Wheldon will be held Sunday
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IndyCar launches a formal investigation into Sunday's fatal accident
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The two-time Indy 500 winner was testing a safer IndyCar in the weeks before his death
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Fellow driver Dario Franchitti says the Las Vegas speedway is "not a suitable track"
"The safety of our drivers, their crews, @placeholder staff, racetrack staff and spectators is always our paramount concern," IndyCar said in a statement, declining to comment further on the probe.