A tip about a planned shooting led to increased security at the Northern Valley High School campuses in Demarest and Old Tappan.
Police are not taking any chances, and for a second day in a row, students and staff must walk through metal detectors. Students are also not allowed to leave the building for lunch, free periods or for any reason.
Police say someone claims to have overheard four students planning a shooting on the Demarest campus this week.
Heightened security at the schools is expected through Friday.
At Old Tappan, staff and students have been directed to report any unusual or suspicious activity to the building principal or assistant principals.
"In consult with law enforcement officials we urge all staff and students to maintain their regular school schedules this week, as there is no credible evidence to support the tip at this time," Superintendent Jan Furman said.
Northern Valley Regional High School www.nvnet.org/