Students wait in the stands at the football field at Gardendale High School during an emergency shutdown on Monday. Law enforcement agencies said the evacuation was due to the discovery of a “suspicious bag” found on campus, later described by authorities as a bomb threat. After further investigation, authorities said the threat was a false alarm.

Students wait in the stands at the football field at Gardendale High School during an emergency shutdown on Monday. Law enforcement agencies said the evacuation was due to the discovery of a “suspicious bag” found on campus, later described by authorities as a bomb threat. After further investigation, authorities said the threat was a false alarm.