Police are guarding Maple Shade High School this week as the Burlington County district investigates "possible threats" on social media from students and other community members, the superintendent said in a letter to parents.

Videos and photos circulating on social media show girls smiling while wearing blackface, a student saying the N-word into a cell phone camera and a Snapchat message exchange in which someone tells a peer to "go tf back to Africa."

"Police and school administration are investigating all issues of derogatory statements, racism and violence," Superintendent Beth Norcia said in the letter posted Tuesday on the district's website. "We are following our Harassment, Intimidation, and Bullying Policy and consequences for behavior have been and will continue to be administered."

Students must show their identification badges when entering the school this week, and visiting parents also have to show ID to office staff, the letter said.

District officials this week met with students to talk about uniting the school community, and administrators and student leaders planned to address classes about diversity and the pitfalls of social media, according to the letter.

The district asked parents to monitor their children's social media activity and talk to them about offensive language and posts. Norcia said officials plan to hold forums to talk about coming together as a community and will share details when they are available.

Maple Shade's school district is 63 percent white, 19 percent Hispanic, 13 percent black and 4 percent Asian, state Department of Education data shows.

"The only way for us to all start the healing process is for the posting of negative comments to stop and engage in productive conversations," Norcia said in her letter. "We need to bring everyone together, not apart."

Norcia and Maple Shade police did not immediately respond to requests for additional information.

Marisa Iati may be reached at miati@njadvancemedia.com. Follow her on Twitter @Marisa_Iati or on Facebook here. Find NJ.com on Facebook.

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