Schools nationwide are seeing an increase in violent threats since the Parkland, Florida, school shooting.
Since 17 people died in the shooting at Marjory Stoneman Douglas High School, at least 328 violent incidents and threats have been reported, according to the Educator's School Safety Network. The group says California leads with the highest number of threats.
So some schools are boosting their security efforts.
Four schools in San Diego County increased security measures Thursday after receiving multiple threats on social media. And last week, New York Gov. Andrew Cuomo ordered state police to patrol schools.
A former FBI profiler told The Washington Post that threats and false alarms often increase after a national tragedy.
Multiple students have been arrested in connection with copycat threats. School officials say one in Arkansas threatened to "shoot up the high school like they did in Florida." They say police concluded the student didn't plan to follow through on the threat.
