This story originally appeared on 6abc.
A disturbing trend has Philadelphia-area schools on high alert as threats of violence continue to circulate on social media.
The threat, which is primarily being fueled on social media, has many school districts increasing police presence Friday.
Earlier this year, TikTok challenges encouraged students to destroy school property.
Now there’s another one spreading nationwide. It started out as a challenge to ditch school, which morphed into a threat of violence at schools on Friday, December 17.
On Thursday night, the Southeast Delco School District announced it would be closed Friday due to “safety concerns.”
“Local police are still investigating the issues that have led to tomorrow’s closure. We will continue to work with them throughout the weekend in an effort to maintain a safe learning environment for all,” said the district in a statement.
In Upper Darby, Superintendent Dr. Daniel McGarry says he and other officials didn’t feel that was necessary for their schools.
“Years ago, not being as well-versed in handling these situations, I think we would’ve reacted a little bit differently. But now our number one objective is to keep schools open and keep kids safe,” said McGarry.
At Sandy Run Middle School in Upper Dublin, officials say a suspicious message was found on a bathroom wall.
A letter to families said an increased police presence will be at Upper Dublin schools as a precaution on Friday, and police are investigating the message in the bathroom.
Action News spoke with a public safety expert who says there are some red flags you can look for at home and in your community.
“If you see a change in behavior in a student who is experiencing something profound. It could be deep depression. It could be anxiety. It could be them mentioning or displaying a weapon. It could be they’re talking about suicide. Any kind of self-harm discussions. Please don’t keep that inside,” said Dr. Larry Barton, a professor of public safety at the University of Central Florida.
Phoenixville, Upper Moreland, Philadelphia and other school districts have notified parents about the increased police presence in light of the threats.
In a statement on Twitter, TikTok said it was working with law enforcement to investigate.
“We handle even rumored threats with utmost seriousness,” the statement said, “which is why we’re working with law enforcement to look into warnings about potential violence at schools even though we have not found evidence of such threats originating or spreading via TikTok.”