SILVER SPRING, Md. (WDVM) — A 15-year-old is in custody after a tip alerted police to a potential threat at Northwood High School on Wednesday.

Staff at Northwood High School were tipped off anonymously. They found two rounds of ammunition after a self-search on the student. After police were contacted, the student fled.

Northwood High School went into a shelter-in-place and Forest Knolls Elementary School was placed on lockdown. A K-9 search found a handgun off of school property. Police said that they do not currently know whether or not this gun was the student’s.

The student was taken into custody within an hour of the shelter-in-place. He was unarmed at that time.