It happened before 8:00 a.m. Thursday on Route 13 at Christiana Road.
RELATED: Photos from the crash
Police say three vehicles collided in the northbound lanes.
One victim were trapped inside a vehicles and had to removed by rescuers.
Seven people were taken to Christiana Hospital in stable condition, including three children.
A 30-year-old woman suffered chest and facial injuries and possible head injury.
A 2-year-old girl suffered minor lacerations.
Three lanes of Route 13 North were closed as police investigated and crews worked to clear the scene.