By Madeleine Wright

BERWYN, Pa. (CBS) — Concerns over student safety forced Conestoga High School to switch to virtual learning Monday.

Students at Conestoga High School are divided on face coverings. Some students want the mask mandate to stay. Others want to get rid of it.

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The confrontation between these two groups of students on social media has gotten ugly. Now the school district is responding.

Turmoil at Conestoga High School is forcing administrators to take drastic action.

On Sunday, the Tredyffrin/Easttown School District notified parents that students at the high school would be attending classes virtually, rather than in person, for student safety on Monday.

“It’s scary because there was also some sort of threat and that’s what the school is responding to,” parent Jessica Lee Tinneny said.

In a statement, the superintendent and principal wrote: “We have seen threatening statements directed toward other students, including racist and homophobic slurs and insults.”

Andrew McLellan says his son Hayden was on the receiving end of those racist slurs on social media.

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“I hate you privileged-a white crackers,” Andrew McLellan said, recalling the threat.

Hayden helped organize a walkout on Friday.

Large groups of students left class to protest the school’s mandatory mask rule. Hayden wants masks to be optional.

“Our school newspaper, The Spoke, has labeled our walkout as anti-mask. I don’t think that’s what it is. It’s a pro-choice, pro-optional mask-wearing. I would never ask anyone to take a mask off or force them to wear one,” Hayden said.

On Sunday, the district said in a statement: “During tomorrow’s day of virtual instruction, we ask for a period of calm and cooperation as we prepare to reunify as a school community. We know Conestoga will rise to the challenge as we have done in the past.”

“It’s disappointing that we can’t get it together as a community,” Tinneny said.

Police say they were called to investigate three incidents that happened over the weekend in which students made some comments online that were perceived as threats, but officers determined none of those were real threats.

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School is back in person Tuesday on a two-hour delay.

Madeleine Wright