(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.
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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