(LITCHFIELD, Ill.) -- At least one person was killed after a double-decker Megabus crashed Thursday on a highway between Chicago and St. Louis, the bus company said. More than 30 others were hospitalized.
Illinois State Police said the dead passenger was a woman who had been seated in the front upper section of the bus, above the driver.
Authorities told ABC News that they believed the cause of the wreck was a blown tire.
The bus, which had 64 passengers listed on its manifest, according to the state police, slammed into a concrete bridge support on Interstate 55 Thursday afternoon near the town of Litchfield, Ill. The company said it was headed to St. Louis and then Kansas City.
Thirty ambulances, five helicopters and seven fire departments were sent to the scene, the state police said.
A spokesperson for St. Francis Hospital in Litchfield told ABC News that it had received 21 patients.
Three other passengers were taken to Staunton Hospital and another three to Hillsboro Hospital. In addition, some passengers were taken to Memorial Hospital in Springfield.
The bus, according to a Megabus spokesperson, was traveling along a route between Chicago, St. Louis, Columbia and Kansas City. Litchfield, the site of the wreck, was about 55 miles north of St. Louis.
The National Transportation Safety Board said it was monitoring the situation, but had yet to make a decision on whether to launch a full investigation.
In a statement, Megabus said: "Safety remains our number one priority. The throughts and prayers of our entire staff go out to the passengers involved. Megabus.com will continue to provide more details as they become available."
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