HILLSDALE — Swastikas found at Pascack Valley Regional High School on Tuesday prompted the school to close areas of the campus and issue alerts to district parents.

The three swastikas were found by staff members Tuesday morning, said the school's director of technology and communication, Paul Zeller. He said officials are not disclosing where at the school the anti-Semitic markings were found.

The Hillsdale Police Department was contacted, Zeller said. The school is in Hillsdale, but draws students from Hillsdale and River Vale.

The swastikas were found one day after the regional district's Board of Education meeting where a previous swastika incident was discussed. That one occurred earlier this school year.

In the first incident, both swastikas were found in boys' bathroom stalls, school officials said.

Parents received a letter via email on Tuesday afternoon from Pascack Valley Regional High School District Superintendent P. Erik Gunderson regarding both incidents.

"We cannot let an individual, or small group of individuals, who spreads a message of hate, become a cloud casting a shadow over our wonderful community. Pascack Valley's students and educators strive toward mutual respect and understanding, which has and continues to shine in so many ways," Gunderson said in the letter.

"In light of the recent events in Pittsburgh, and now in the halls of our own school, I urge everyone — students, parents and staff members to talk about how we can all be more caring, compassionate and respectful.

"We also ask that if you ever encounter a person or environment of intolerance, violence or hate that you share your concern with someone from our staff so we can assist," Gunderson said in the letter.

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Gunderson told parents in the letter that he has contacted local religious leaders and the Anti-Defamation League regarding the incidents. The staff has also reached out to the Student Government Association about working with students to teach sensitivity.

River Vale resident Elmar Leibfried was surprised to hear about the incident.

"I find it kind of unbelievable," said Leibfried, whose son attends Pascack Valley High School. "Usually the kids in this area are good about and acceptable of people's differences."

Jean Chen of Hillsdale, whose son graduated from Pascack Valley High School in 2014, said the school had another issue several years ago, involving anti-gay bias. Chen said she was disappointed to learn about the swastikas

"It's a small group and it's unfortunate," Chen said.