An electrical fire in a utility tunnel system beneath Edgemont Junior/Senior High School forced the evacuation of about 900 students and led to the school’s closure Thursday.

According to Greenville Fire Chief Gus Spedaliere, responding crews arrived to find smoke coming from the administrative building. Investigators determined the source of the smoke was a tunnel system beneath the structure.

Chief Spedaliere said the school is connected by tunnels used for utility purposes. As crews investigated further, they found the tunnels filled with smoke and determined there was an active electrical fire underground.

Officials said about 900 students were first evacuated to an upper field on campus before being relocated to Seely Place Elementary School.

No injuries were reported.

School officials declined to comment.