During a meeting, teachers were nearly scared to death when two masked men came into the room with guns and started firing blanks as part of a drill.
The teachers were not warned beforehand that a drill would take place, and students weren't present.
The meeting was held on April 26 and consisted of 15 instructors at the Pine Eagle Charter School in Halfway, Oregon.
School officials said the teachers did not respond well to the drill, and most of them would have been killed if it had been a real gunman.
The principal said they will be training the teachers to better respond to similar situations.
During the meeting, two men wearing black masks and hooded sweatshirts stormed in and began shooting the blanks.
It took awhile for the teachers to realize the shooting was not drawing blood and it was part of a test.
"I'll tell you, the whole situation was horrible," teacher Morgan Gover, 31, said.
"I'm in charge of a pile of kids. It made me analyze as a teacher what my role is for these babies."
The town is located in northeast Oregon and has a small population of 288.
"We are so remote," Gover said. "We are going to have to take care of ourselves."
One teacher was so frightened by the ordeal that she now locks her classroom door throughout the day.