Students are heading back to class today at FDR High School in Dutchess County after a false alarm forced students and staff to evacuate.

First responders say they were called to the school early Monday for reports of a strange smell in the building.

Staff determined the odor was coming from a heating source.

Out of an abundance of caution, the building was cleared.

Fire officials checked out the building and determined the smell was caused by a small backfire in one of the boilers. No carbon monoxide or any other gases were present.

Students were allowed back inside, and classes continued as normal.