GARFIELD — Classes were canceled at one school and security was tightened at another following threats made against each.

Classes at Garfield High School were canceled "due to a threat that is currently being investigated by Garfield Police," according to a message tweeted on the school's Twitter account late Monday night. All other Garfield schools will be open as normal Tuesday.

Security at Manville public schools was increased for Tuesday after the district was notified of a "potential threat to the safety of Manville High School students," according to a letter sent by superintendent Robert Beers.

Beers said an investigation by Manville Police and the Somerset County Prosecutor's Office determined it not to be credible.

The nature of the threats was not disclosed.

Anyone making a threat to a school faces a five- to 10-year prison sentence and a possible fine of $150,000. The potential punishments in New Jersey against threats were tightened in 2015 following a series of "swatting" events that required full responses by law enforcement and first responders to threats that turned out to be false.

New Jersey’s Suspicious Activity Reporting System, or SARS, allows all agencies from local police to the Attorney General's office to work together when an incident occurs.

New Jersey Attorney General Gurbir Grewal said real-time communication with different departments and agencies is critical.

"If we sit on this information in our little silos, if Cape May doesn’t share with Bergen, if Bergen doesn’t share with the State Police, then we’re not effectively addressing the problem," Grewal said.

Previous reporting by David Matthau was used in this report.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ.

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