A 13-year-old student was hit by a tractor trailer after getting off of a school bus in Gray on Tuesday, according to the Cumberland County Sheriff’s Department.

The male teenager, who has not been identified, had gotten off the bus and was crossing in front of it when he was struck by a tractor trailer at around 2:27 p.m. according to Sheriff Kevin Joyce. He was semi-conscious when officials arrived on scene, and was taken to Maine Medical Center with serious injuries.

The bus lights and stop sign were functioning and activated at the time of the crash. The vehicle was being driven by 62-year-old Joyce Hamilton of New Gloucester.

The bus had been carrying 17 students at the time the student was struck. They were taken off of the bus and brought back to the middle and high school campuses, according to MSAD 15 Superintendent Craig King. Counselors will be available at the schools, CBS 13 reported.

The tractor trailer, owned by Farmington-based Bard Trucking, was being driven by Jeffrey Lane, a 49-year-old Farmington man. The circumstances of the crash remain under investigation, and both vehicles will undergo a full inspection as part of the crash reconstruction process.

Route 100 is closed in the area of 135 Lewiston Road. Southbound traffic on Lewiston Road from New Gloucester will be diverted to Weymouth Road.