Police say a 15-year-old Marcos De Niza High School student has been arrested after starting a fire at school Thursday morning.
Tempe police spokeswoman Molly Enright said the fire was found burning inside a gym locker around 11:39 a.m. at the school near Guadalupe Road and Lakeshore Drive.
Enright said a school employee inside the building smelled smoke, called 911 and then extinguished the fire.
Officials said the fire was confined to a small area and had no time to spread throughout the building.
When fire crews arrive, they searched the building to make sure all the students made it out safely.
Tempe police detectives determined a 15-year-old student at the school intentionally started the fire.
Enright said the student was arrested and charged with arson, aggravated criminal damage and interference with or disruption of an educational institution.
Police said the school employee who put out the fire suffered from smoke inhalation and was admitted to the hospital for observation.
Authorities said the investigation is ongoing.
The student's name and photo are not being released because he is a juvenile.