Threats made to school districts throughout the region are increasing at an alarming pace — a disturbing trend with a complex foundation that includes copycat crimes, more reporting, and the delicate task of dealing with immature students who simply make bad decisions.

It's not just happening here. Across the nation, school districts and law enforcement officials are responding to more threats that have teachers, students, and parents on edge.

Just days ago, police in Stafford, Ocean County, announced the arrests of nine intermediate school students who they said talked of "becoming active shooters." Taken into custody were 11- and 12-year-old boys.

In a Facebook post, Stafford Police Chief Thomas Dellane and School Superintendent George Chidiac said there would be "zero tolerance" for threats of violence in the schools and announced: "All reports will be fully investigated, and all threats will be prosecuted to the fullest extent."

In York County,  a 13-year-old girl was charged last month with making terroristic threats after police said she was overheard saying, "Don't come to school tomorrow," and that "the person" would be there all week. The remarks were taken so seriously that the school closed for three days. Police said the girl showed investigators how she made threats using social media.

The rise in reported threats has roiled school officials across the region.

"We certainly do see spikes like this after incidents such as those in Florida, but this is the most pronounced spike we have seen," said Ryan Tarkowski, a spokesman for the Pennsylvania State Police. Since the Valentine's Day massacre in Parkland, Fla., Pennsylvania police have tracked more than 75 school threats. Not every incident was a real threat, but police and administrators are sending clear messages that regardless of whether students are joking or serious they will be held accountable for what they say.

"We would much rather have a report and it turns out to be nothing rather than not having a report and it turns out to be a tragedy," Tarkowski said, adding that school threats have always carried a high level of urgency to investigate. As a result, students are facing criminal charges, schools have been put on lockdown, and in the extreme measure, classes have been canceled.

Steve Baker, a spokesman for the New Jersey Education Association, said parents and school faculty are "understandably are on edge. It [Parkland] was a horrible incident and it raises many concerns."

Children and teachers, Baker said, must be in a safe environment.

In Gloucester County, Delsea Superintendent Piera Gravenor recalled being in South Florida for vacation when the students were killed at Stoneman Douglas High School. It was horrifying, she said, and it felt too close to home.

Late last month, police arrived at Delsea Regional High School to investigate reports that two students had talked about shooting up the school. They told authorities they were only joking, but both were charged with making terroristic threats.

Gravenor said at the time that she would rather be cautious than fail to act in a serious situation.

Just days later, the school district closed after two emails were sent to teachers, threatening shootings at two nearby schools. While the threats were under investigation, elementary schools in Franklin and Elk Townships closed for the day, as did the shared middle and high schools that are operated by the Delsea district. A 10-year-old student was later charged with sending out the threatening messages.

The Educators School Safety Network, a nonprofit organization that gives educators a voice in keeping schools safe, created a live tracker of school incidents and threats. Typically, the group reports 10 threats a day across the nation. More than 800 incidents have been reported nationwide since Parkland, with more than 70 on some days, the group said.

"The uptick we've seen since Parkland is very troubling," said Amanda Koinger, director of operations for the organization. The group uses Google alerts to aggregate incidents reported in the media. Even before the Parkland carnage, she said, the number of threats was increasing. "We're on a scary upward trajectory."

In the 2016-17 school year, the organization reported more than 2,220 threats against schools. Koinger said there are significantly more reported threats than are included in that count. Neither law enforcement nor school officials compiles national statistics, she said. In its ranking, the group identifies New Jersey as a state of high concern and Pennsylvania as one of moderate concern.

Across the nation, the group identified 15 threats in which students were found to have been collecting guns and ammunition, but authorities were able to thwart their plans. The vast majority of threats are not real, she said.

Nevertheless, she said, "we have to get kids to start to understand that this is not something you joke around about."

She urged schools to offer training for teachers and students on how to deal with threats and violence and said educators should be proactive in identifying troubled students to address problems up front rather than being reactive.

"Today, in every American classroom, every teacher has a kid who they are concerned about," Koinger said. "They have to learn how to assess. It's about prevention."