A bus was turning left from Summit Bridge Road onto Howell School Road when it was struck by a tractor trailer that was traveling north.
The collision caused the bus to overturn onto its side.
The bus was carrying a group of Sorority Sisters from the University of Delaware.
Police say there were approximately 40 passengers between the ages of 18 and 22 on the bus when the crash occurred.
Nine of the passengers were taken by ambulance to Christiana Hospital. Two were admitted with non-life threatening injuries.
The remainder of the forty passengers were taken to area medical centers by private vehicles and treated for minor injuries.
56-year-old John Faverio of Wilmington, Delaware was driving the bus. Police say 26-year-old Roberto Figueroa-Gomez was driving the tractor-trailer and was issued a traffic summons for failing to stop at a red light.
Both drivers were properly restrained and were not injured in the crash.
Authorities from the University of Delaware as well as Delaware State Police continue to investigate.