The bus driver who left a 4-year-old student unattended on a bus for four hours Tuesday did not even turn around to see the child still there, an investigation revealed.

The student is enrolled in the Florence Bowser Elementary School Early Start program.

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 any children left onboard, which is “consistently emphasized at all of the drivers’ training,” Bradshaw said.

Initially, it was assumed the boy had fallen asleep and sunk below eye level in his seat, but the video showed the driver simply never looked behind to see the boy still there.

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.

Bradshaw added that the boy’s teacher asked classmates if they had seen the boy on the bus, but the children 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 have viewed 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.