MURRYSVILLE (KDKA) – Franklin Regional Middle School maintained heightened security Tuesday after a bomb threat was found on a bathroom wall Monday afternoon.

All after-school activities for Monday were canceled and early Tuesday activities were canceled as well.

Police and bomb-sniffing dogs swept the area on Monday.

On Tuesday, students’ bags were searched on the way into and out of the building.

School officials said typical attendance is around 97 percent. The week before holidays that usually drops to around 90 percent.

Tuesday’s attendance was closer to 80 percent with many students coming in late. The absences will be considered excused.

Police and school officials are still investigating who initiated the threat.