One passenger was killed and at least 32 injured Thursday when a double-decker Megabus slammed into a concrete pillar along Interstate 55 in southern Illinois, state officials told NBC News. The bus company confirmed that 81 people were booked for the trip from Chicago to St. Louis but just 64 on board. At least several, they said, were in critical condition, and at least three local hospitals were accepting patients. Illinois State Police said there were no confirmed fatalities, but the exact number of those injured and the total number of passengers was not yet confirmed. The wife of one passenger posted on Facebook that the bus had blown a tire, causing it to careen off the road into the pillar, NBC 5 Chicago reported. Police said at 30 ambulances, five helicopters and seven fire departments responded to the crash. The interstate was shut down in both directions after the crash, but northbound lanes later reopened.