Megabus, which operates double-decker buses, said the vehicle, made by the Belgian Van Hool company, was only a year old, the Chicago Tribune reported. The bus "had passed a full preventative maintenance check within the past week," Megabus spokeswoman Amanda Byers said.
The bus was headed from Chicago to St. Louis when the driver apparently lost control on Interstate 55 south of Springfield, Ill., and hit a bridge abutment.
Adititi Avhad, 25, a native of Mumbai who had qualified as a dentist and was studying for a master's in health administration at the University of Missouri, was the only person killed. Illinois State Police said at least half of the 64 passengers were injured, and the driver and several passengers were trapped on the bus for some time.
Michael Martin of Minneapolis, who was on his way to Kansas City to visit relatives, said local emergency workers responded quickly -- "they were here in no time" -- and drivers who saw the crashed bus stopped to help pull people out of the wreckage. Martin himself suffered only minor injuries to his head and neck.
"I flew forward and my glasses were smashed into the back of the seat in front of me," said Eliana Siegal, 16, of Chicago. "People were panicking and babies were crying -- a woman across the aisle from me was screaming that her leg was broken."