A 17-year-old student was arrested after bringing a gun and drugs to a North Philadelphia high school on Monday morning.

The arrest happened at Thomas Alva Edison High School on West Luzerne Street just before 9 a.m. as students returned to class for the first day of school. 

In a letter sent to parents and guardians on Monday, Principal Lillian Izzard said the gun was found by a school safety officer who was operating the metal detection machine. 

"While we are fortunate that this item was identified and confiscated, it is still an item that is prohibited on any School District of Philadelphia property and, per District policy, we placed the school on a hold to secure the building while a thorough search for other potential prohibited items on school grounds was conducted," Izzard said in the letter. "After finding none, we were able to resume our normal school day." 

According to police, officers recovered a silver handgun and narcotics. The 17-year-old was arrested on weapons charges and narcotics violations.

The incident is under investigation.