Four students from Fallsmead Elementary School in Rockville sustained minor injuries when an 80-year-old driver hit their school bus head-on Friday morning, according to authorities.

The car’s driver was hospitalized with serious injuries, according to Montgomery County Fire and Rescue Service spokeswoman Beth Anne Nesselt.

The driver, a Potomac man, was charged with failure to control speed to avoid a collision and crossing the center line of the roadway, said Rockville Police Lt. Eric Over. He is in stable condition and has been able to talk to investigators, Over said.

There were 37 students on the bus, said Dana Tofig, a Montgomery schools spokesman. The four with minor injuries “were taken to the hospital as a precaution,” Tofig said.

The other students were evaluated by a nurse once they reached school and officials were calling the students’ parents, Tofig said.

He said school officials had been told the driver of the other vehicle may have passed out before the collision, which occurred near the intersection of Wootton Parkway and Hurley Ave. in Rockville.

Over said the bus was traveling south on Wootton nearing the intersection when the man’s Chevy Cavalier came onto the wrong side of the road.

“It’s unknown what caused the driver of the vehicle to cross the center line,” and that remains under investigation, Over said.

This item has been updated.