Police said the 17-year-old from N.J. gained access through a roof hatch.
A social media posting led police to charge a teenager with burglary at Hatchery Hill School, Hackettstown police said.
Police on Wednesday arrested the 17-year-old Mansfield Township boy, whose name was not released because he is a juvenile.
Police said the boy entered the elementary school at 398 Fifth Ave. through a roof hatch between 7 a.m. to 7:30 a.m. Tuesday and set off a motion alarm. The school was closed and no one was in the building, according to police.
Police said the boy then fled through a back door.
A social media tip alerted police to the teen responsible for the crime, police said. Nothing was stolen from the school, they said.
The teen was charged with third-degree burglary and fourth-degree criminal trespassing. He was released pending a court appearance.
The Hackettstown Police Department praised the public in coming forward with information that led to the arrest.
Pamela Sroka-Holzmann may be reached at pholzmann@lehighvalleylive.com. Follow her on Twitter @pamholzmann. Find lehighvalleylive.com on Facebook.