SPRINGFIELD, Ill. (TNND) — The driver of a vehicle that crashed through an after-school building in Illinois on Monday and killed four students was not intoxicated, according to preliminary toxicology test results.

Police say the driver of a car that barreled through a building used for a popular after-school camp in central Illinois, killing three children and a teenager, may have had a medical emergency.

Four children died Monday and others were injured when a vehicle plowed into a building housing an after-school program in the central Illinois town of Chatham, state police said. Illinois State Police said officers were called to the YNOT Outdoors Summer and After School Camp,