Authorities evacuated Pershing Middle School Thursday after reports of a noxious odor in at least one classroom, according to campus officials.

Hazardous-materials personnel were called around noon to the Lake Murray-area campus located at 8204 San Carlos Drive, with school officials reporting several students felt lightheaded due to the smell.

The San Diego Fire-Rescue Department gave an all-clear at the school shortly before 4 p.m. No hazards were found, a city spokeswoman said.

It’s unclear what caused the smell. Unconfirmed reports indicate it may have emanated from chemicals used as part of a science lesson.

There were no reported injuries and none of the affected youths needed hospital care.

–Staff