Police were on hand Monday as students returned to a New Jersey high school that prosecutors say was the target of a "Columbine-like" plot, which was uncovered when authorities found a cache of weapons in one teen's home.
Officials said the police presence was to reassure students and parents that Bridgewater-Raritan High School was safe.
Principal James Riccobono was to offer words of encouragement during an address to all 2,900 students before classes Monday.
Counselors were also on hand.
Authorities said a 16-year-old junior was arrested Thursday after a police resource officer at the school was told the teen was planning an attack.
Authorities said they found shotgun shells, bullets, black powder and explosive devices in the teen's home.
Officials also arrested a 17-year-old Immaculata High School senior, who is a competitive target shooter.