Four people, all of them children or teenagers, were killed and several others were injured on Monday when a car crashed through an after-school center in Chatham, Ill., a village just south of Springfield, the State Police said.

The victims are believed to be 18 years and younger, the Illinois State Police Department said in news release.

The car struck three of the victims outside the building and the other inside of it, the police said. Several people were taken to the hospital, and at least one person was airlifted, the authorities said.

There was no additional information on the injuries on Monday evening or the ages of those injured, said Melaney Arnold, a spokeswoman for the Illinois State Police.

The driver, who has not been publicly identified, was not injured and was undergoing an evaluation at the hospital Monday evening, the State Police said. No one else was in the vehicle, the police said.

Officers with Chatham Police, Chatham fire and other agencies responded to a call Monday afternoon of a vehicle driving into Y.N.O.T. and After School Camp, the State Police said

According to the police, the driver drove into the east side of the building, striking multiple people outside and then continued driving through the building, hitting more people inside before exiting through the building on the west side.

The Illinois State Police and the Chatham Police Department are investigating the crash. It was not immediately known what caused the crash.

Gov. JB Pritzker of Illinois said on social media that his administration was monitoring the situation.

This is a developing story.

Neil Vigdor contributed reporting.