(ABC 6 News) — Threats to Minnesota schools are on the rise with new state data showing they are more than four times higher this school year than last fall.

The Minnesota Bureau of Criminal Apprehension says through the first few weeks of September, there were 14 investigations involving school threats.

During the same time a year ago, there were three reported to the BCA. Some teachers say the growing concern has become a constant stress.

“Honestly, I think most teachers live their lives with complex PTSD, to be perfectly honest,” said teacher Becka Thompson. “I have been in schools that have gotten shot up at the door, and then you’re on a lockdown that way.”

Just last week, Mason City Police investigated a possible school threat after concerned parents saw a suspicious Snapchat post. It was later determined there was no threat to the school.