Threats were received by schools in at least three municipalities in New Jersey on Friday.

Private and public schools in Lawrence in Mercer County dealt with threats. Schools were evacuated in Jersey City and placed on lockdown in Linden.

Lawrence police said an adult male called the office at the Benjamin Franklin Elementary School around 10:35 a.m. and said six pipe bombs were in the building. The building was evacuated and children sent to another location. The Lawrenceville Elementary School was locked down when an adult male said he was headed to the school with a rifle. The other schools in the district were also locked down, according to police.

Students at the Lawrenceville School on Route 206 in Lawrence were taken to the Bristol Myers Squibb facility, according to a message on the school website. The school did not disclose a reason for the evacuation but an update posted at 1:25 p.m. said the school was deemed safe and students were returning to campus.

Classes and sports activities were canceled for the rest of the day, according to the alert.

After the buildings were searched they were declared safe and students returned to the public schools by noon. Police considered the cases to be "fraudulent and were classified as swatting incidents."

The Union County Bomb Squad and K9 units responded to a bomb threat against Linden High School on Friday morning around 8:45 a.m., according to city police. The school was placed on a lockdown while a search of the school was conducted.

The lockdown was lifted at 11:15 a.m.

“It is unfortunate that our children's education has to be disrupted by reckless threats like these,” said Linden Police Chief David Hart. “Each of these threats are taken very seriously, and we will use every resource at our disposal to ensure that the person responsible is brought to justice.

Earlier in the day, Jersey City police responded to both County Prep High School and McNair High School on threats of a bomb in each school. Both schools were immediately evacuated and have been deemed safe.

"Both schools were immediately evacuated and have been deemed safe," Jersey City police spokeswoman Ashley Manz said.

It's not clear if any of the incident are related.

A "swatting" threat made against two schools in Manasquan on Monday led to a 90 minute delayed opening.

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

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