A 4-year-old student enrolled in the Florence Bowser Elementary School Early Start program was left unattended for four hours on a school bus Tuesday morning after he fell asleep and was not found by his bus driver.

The bus driver dropped students off at Florence Bowser, and then went to park the vehicle at Northern Shores Elementary School around 9 a.m., according to Bethanne Bradshaw, public information officer for Suffolk Public Schools.

The driver failed to walk to the back of the bus to check the seats for sleeping children, which is “consistently emphasized at all of the drivers’ training,” Bradshaw said.

Another bus driver found the boy around 12:55 p.m. after returning to get a bus from Northern Shores.

The boy was brought back to Florence Bowser, where he was given lunch and seen by the school nurse. His parents were immediately called.

Bradshaw said the boy seemed to be unharmed, and had a packed lunch to eat while on the bus.

Bradshaw added that the boy’s teacher asked classmates if they had seen the boy on the bus, and classmates could not recall.

“We regret that this had to happen, and we will continue to do everything we can to prevent these things from occurring again,” Bradshaw said. “We take very seriously our job to protect a child, all 14,000 we have in our school division.”

The bus driver has been placed on administrative leave until the school system’s investigation in complete. As a part of that investigation, officials will watch the video footage from the bus’s video camera. Additionally, Social Services and Child Protective Services are investigating the incident, because a child was left unattended.