The parents of a young woman who was killed in a double-decker bus crash in Illinois are suing the bus company over the death of their daughter.

The suit was filed by the parents of 25-year-old Aditi Avhad, a woman from India who was pursuing a graduate degree at the University of Missouri. They were all passengers on the bus when it crashed into a concrete pillar on Interstate 55 in Litchfield, Illinois, just south of Springfield, in early August. Avhad's mother suffered a broken hip and a broken leg in the accident.

Named as defendants in the lawsuit are Megabus USA LLC, Chaoch Leasing Inc., Coach USA Inc. and the bus driver, Preston Taylor.

The bus was en route from Chicago to Kansas City at the time of the crash, with stops scheduled in St. Louis and Columbia, Missouri.

Megabus has not commented on the lawsuit.