Teachers and students endured a scare at Central Middle School in Long Hill Wednesday after a crossing guard spotted suspicious backpack.

Police evacuated people in the school and residents in nearby homes after the crossing guard spotted the black bag unattended in front of the school. School administrators moved the students to St. Vincent De Paul Catholic School while the Morris County Sheriff?s Bomb Squad investigated the bag. Some parents picked up their children after a reverse 911 message notified them of the incident.

After three hours, the bomb squad found the bag to be harmless. Some students returned to classes after the scare. Police are now trying to figure out who left the bag in front of the building. They are also investigating the possibility the bag could be connected to recent bomb threats made against the school.