FRISCO, Texas -- Several children and one adult were sent to the hospital after a teen driver crashed a car into a daycare Thursday afternoon.

The crash happened at the Primrose School of Frisco at Main and Teel in the 9100 block of Teel Parkway. The 17-year-old driver hit the accelerator, instead of the brake pedal, crashing into the gate outside of the school, officials say.

"Several kids were either moving into the classroom or out of the classroom, we're not sure which," said Kevin Haines, captain with the Frisco Fire Department.

A medical helicopter transferred two of the children to Children's Medical Center Dallas.

As of Friday morning, one child remained in critical condition in the ICU, while three others were admitted overnight to the trauma floor. They are expected to be released sometime Friday.

"Anytime you have a child that is hit, the first concern that comes to mind is head injuries," said Haines.

Parents scrambled in the parking lot to pick up their children. Some parents came by to pick up their children's stuff.

"I hope they're doing ok, and I hope nobody was seriously hurt," said Patrick Ludley, a parent.

The school released the following statement:

“We are heartbroken about the accident that happened today at our school, injuring multiple children and teachers. Our Primrose community is our family and nothing is more important to us than the safety and well-being of the children entrusted to our care. We are incredibly proud of how our teachers and staff responded today and we are grateful for the police and paramedics for their swift action as well."We’re standing side-by-side with the affected families and are currently here at the hospital. We are praying for the medical teams caring for these children and their families and ask that you do too.”

Officials say the 17-year-old driver, who had his driver's permit, was not injured and is cooperating with officials. The father of the driver told WFAA that he was sitting in the passenger's seat when the crash happened.

The teen was on his way to driving school across the street. The father said his son is incredibly sorry and was shaken up by the crash.

The scene remains under investigation.