DUMONT, N.J. (CBSNewYork) — Classes resume with extra security at Dumont High School in Bergen County Tuesday after an alleged online threat forced a lockdown.

Dumont police say it was just before noon Monday when the security threat was posted on social media.

“We immediately placed the school in a lockdown due to the fact the threat was a student who planned to shoot up the school,” said Dumont Police Chief Mike Connor.

As word spread, terrified parents arrived at the school not knowing what was going on.

“I just want to know what’s going on,” said parent Helen Stevenson. “I want to see her and hold her.”

Heavily armed SWAT teams searched the school room by room as police eventually located the 15-year-old suspect they were looking for in a second floor classroom. He was taken into custody.

Investigators also searched the student’s home, where they said they did recover a weapon.

“From his house, we did retrieve one long gun, one rifle from that house,”said Connor. “It was not with him at the school, it was not on school property.”

Police said who the gun was registered to and whether or not it was legally purchased was part of the ongoing investigation by the Bergen County Prosecutor’s Office.

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